Add m-esr52 at 52.6.0

27 files changed, 8928 insertions, 0 deletions

diff --git a/xpfe/appshell/moz.build b/xpfe/appshell/moz.build
new file mode 100644
index 000000000..5cfe41924
--- /dev/null
+++ b/xpfe/appshell/moz.build
@@ -0,0 +1,42 @@
+# -*- Mode: python; indent-tabs-mode: nil; tab-width: 40 -*-
+# vim: set filetype=python:
+# This Source Code Form is subject to the terms of the Mozilla Public
+# License, v. 2.0. If a copy of the MPL was not distributed with this
+# file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
+MOCHITEST_CHROME_MANIFESTS += ['test/chrome.ini']
+
+XPIDL_SOURCES += [
+    'nsIAppShellService.idl',
+    'nsIPopupWindowManager.idl',
+    'nsIWindowlessBrowser.idl',
+    'nsIWindowMediator.idl',
+    'nsIWindowMediatorListener.idl',
+    'nsIXULBrowserWindow.idl',
+    'nsIXULWindow.idl',
+]
+
+XPIDL_MODULE = 'appshell'
+
+EXPORTS += [
+    'nsAppShellCID.h',
+]
+
+UNIFIED_SOURCES += [
+    'nsAppShellFactory.cpp',
+    'nsAppShellService.cpp',
+    'nsAppShellWindowEnumerator.cpp',
+    'nsChromeTreeOwner.cpp',
+    'nsContentTreeOwner.cpp',
+    'nsWebShellWindow.cpp',
+    'nsWindowMediator.cpp',
+    'nsXULWindow.cpp',
+]
+
+LOCAL_INCLUDES += [
+    '/dom/base',
+]
+
+FINAL_LIBRARY = 'xul'
+
+include('/ipc/chromium/chromium-config.mozbuild')
\ No newline at end of file
diff --git a/xpfe/appshell/nsAppShellCID.h b/xpfe/appshell/nsAppShellCID.h
new file mode 100644
index 000000000..2b0edd4ac
--- /dev/null
+++ b/xpfe/appshell/nsAppShellCID.h
@@ -0,0 +1,10 @@
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsAppShellCID_h__
+#define nsAppShellCID_h__
+
+#define NS_APPSHELLSERVICE_CONTRACTID "@mozilla.org/appshell/appShellService;1"
+
+#endif
diff --git a/xpfe/appshell/nsAppShellFactory.cpp b/xpfe/appshell/nsAppShellFactory.cpp
new file mode 100644
index 000000000..0b6d3c47a
--- /dev/null
+++ b/xpfe/appshell/nsAppShellFactory.cpp
@@ -0,0 +1,56 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/ModuleUtils.h"
+#include "nscore.h"
+#include "nsIWindowMediator.h"
+
+#include "nsIAppShellService.h"
+#include "nsAppShellService.h"
+#include "nsWindowMediator.h"
+#include "nsChromeTreeOwner.h"
+#include "nsAppShellCID.h"
+
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsAppShellService)
+NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsWindowMediator, Init)
+
+NS_DEFINE_NAMED_CID(NS_APPSHELLSERVICE_CID);
+NS_DEFINE_NAMED_CID(NS_WINDOWMEDIATOR_CID);
+
+static const mozilla::Module::CIDEntry kAppShellCIDs[] = {
+  { &kNS_APPSHELLSERVICE_CID, false, nullptr, nsAppShellServiceConstructor },
+  { &kNS_WINDOWMEDIATOR_CID, false, nullptr, nsWindowMediatorConstructor },
+  { nullptr }
+};
+
+static const mozilla::Module::ContractIDEntry kAppShellContracts[] = {
+  { NS_APPSHELLSERVICE_CONTRACTID, &kNS_APPSHELLSERVICE_CID },
+  { NS_WINDOWMEDIATOR_CONTRACTID, &kNS_WINDOWMEDIATOR_CID },
+  { nullptr }
+};
+
+static nsresult
+nsAppShellModuleConstructor()
+{
+  return nsChromeTreeOwner::InitGlobals();
+}
+
+static void
+nsAppShellModuleDestructor()
+{
+  nsChromeTreeOwner::FreeGlobals();
+}
+
+static const mozilla::Module kAppShellModule = {
+  mozilla::Module::kVersion,
+  kAppShellCIDs,
+  kAppShellContracts,
+  nullptr,
+  nullptr,
+  nsAppShellModuleConstructor,
+  nsAppShellModuleDestructor
+};
+
+NSMODULE_DEFN(appshell) = &kAppShellModule;
diff --git a/xpfe/appshell/nsAppShellService.cpp b/xpfe/appshell/nsAppShellService.cpp
new file mode 100644
index 000000000..7e1ddf16c
--- /dev/null
+++ b/xpfe/appshell/nsAppShellService.cpp
@@ -0,0 +1,1001 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#include "nsIAppShellService.h"
+#include "nsIComponentManager.h"
+#include "nsIURL.h"
+#include "nsNetUtil.h"
+#include "nsIServiceManager.h"
+#include "nsIObserverService.h"
+#include "nsIObserver.h"
+#include "nsIXPConnect.h"
+#include "nsIXULRuntime.h"
+
+#include "nsIWindowMediator.h"
+#include "nsIWindowWatcher.h"
+#include "nsPIWindowWatcher.h"
+#include "nsIDOMWindow.h"
+#include "nsPIDOMWindow.h"
+#include "nsWebShellWindow.h"
+
+#include "prprf.h"
+
+#include "nsWidgetInitData.h"
+#include "nsWidgetsCID.h"
+#include "nsIWidget.h"
+#include "nsIRequestObserver.h"
+#include "nsIEmbeddingSiteWindow.h"
+
+#include "nsAppShellService.h"
+#include "nsContentUtils.h"
+#include "nsThreadUtils.h"
+#include "nsISupportsPrimitives.h"
+#include "nsIChromeRegistry.h"
+#include "nsILoadContext.h"
+#include "nsIWebNavigation.h"
+#include "nsIWindowlessBrowser.h"
+
+#include "mozilla/Attributes.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/Services.h"
+#include "mozilla/StartupTimeline.h"
+
+#include "nsEmbedCID.h"
+#include "nsIWebBrowser.h"
+#include "nsIDocShell.h"
+
+#ifdef MOZ_INSTRUMENT_EVENT_LOOP
+#include "EventTracer.h"
+#endif
+
+using namespace mozilla;
+
+// Default URL for the hidden window, can be overridden by a pref on Mac
+#define DEFAULT_HIDDENWINDOW_URL "resource://gre-resources/hiddenWindow.html"
+
+class nsIAppShell;
+
+nsAppShellService::nsAppShellService() :
+  mXPCOMWillShutDown(false),
+  mXPCOMShuttingDown(false),
+  mModalWindowCount(0),
+  mApplicationProvidedHiddenWindow(false),
+  mScreenId(0)
+{
+  nsCOMPtr<nsIObserverService> obs = services::GetObserverService();
+
+  if (obs) {
+    obs->AddObserver(this, "xpcom-will-shutdown", false);
+    obs->AddObserver(this, "xpcom-shutdown", false);
+  }
+}
+
+nsAppShellService::~nsAppShellService()
+{
+}
+
+
+/*
+ * Implement the nsISupports methods...
+ */
+NS_IMPL_ISUPPORTS(nsAppShellService,
+                  nsIAppShellService,
+                  nsIObserver)
+
+NS_IMETHODIMP
+nsAppShellService::CreateHiddenWindow()
+{
+  return CreateHiddenWindowHelper(false);
+}
+
+NS_IMETHODIMP
+nsAppShellService::SetScreenId(uint32_t aScreenId)
+{
+  mScreenId = aScreenId;
+  return NS_OK;
+}
+
+void
+nsAppShellService::EnsurePrivateHiddenWindow()
+{
+  if (!mHiddenPrivateWindow) {
+    CreateHiddenWindowHelper(true);
+  }
+}
+
+nsresult
+nsAppShellService::CreateHiddenWindowHelper(bool aIsPrivate)
+{
+  nsresult rv;
+  int32_t initialHeight = 100, initialWidth = 100;
+
+#ifdef XP_MACOSX
+  uint32_t    chromeMask = 0;
+  nsAdoptingCString prefVal =
+      Preferences::GetCString("browser.hiddenWindowChromeURL");
+  const char* hiddenWindowURL = prefVal.get() ? prefVal.get() : DEFAULT_HIDDENWINDOW_URL;
+  if (aIsPrivate) {
+    hiddenWindowURL = DEFAULT_HIDDENWINDOW_URL;
+  } else {
+    mApplicationProvidedHiddenWindow = prefVal.get() ? true : false;
+  }
+#else
+  static const char hiddenWindowURL[] = DEFAULT_HIDDENWINDOW_URL;
+  uint32_t    chromeMask =  nsIWebBrowserChrome::CHROME_ALL;
+#endif
+
+  nsCOMPtr<nsIURI> url;
+  rv = NS_NewURI(getter_AddRefs(url), hiddenWindowURL);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  RefPtr<nsWebShellWindow> newWindow;
+  if (!aIsPrivate) {
+    rv = JustCreateTopWindow(nullptr, url,
+                             chromeMask, initialWidth, initialHeight,
+                             true, nullptr, nullptr, getter_AddRefs(newWindow));
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    mHiddenWindow.swap(newWindow);
+  } else {
+    // Create the hidden private window
+    chromeMask |= nsIWebBrowserChrome::CHROME_PRIVATE_WINDOW;
+
+    rv = JustCreateTopWindow(nullptr, url,
+                             chromeMask, initialWidth, initialHeight,
+                             true, nullptr, nullptr, getter_AddRefs(newWindow));
+    NS_ENSURE_SUCCESS(rv, rv);
+
+    nsCOMPtr<nsIDocShell> docShell;
+    newWindow->GetDocShell(getter_AddRefs(docShell));
+    if (docShell) {
+      docShell->SetAffectPrivateSessionLifetime(false);
+    }
+
+    mHiddenPrivateWindow.swap(newWindow);
+  }
+
+  // RegisterTopLevelWindow(newWindow); -- Mac only
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppShellService::DestroyHiddenWindow()
+{
+  if (mHiddenWindow) {
+    mHiddenWindow->Destroy();
+
+    mHiddenWindow = nullptr;
+  }
+
+  if (mHiddenPrivateWindow) {
+    mHiddenPrivateWindow->Destroy();
+
+    mHiddenPrivateWindow = nullptr;
+  }
+
+  return NS_OK;
+}
+
+/*
+ * Create a new top level window and display the given URL within it...
+ */
+NS_IMETHODIMP
+nsAppShellService::CreateTopLevelWindow(nsIXULWindow *aParent,
+                                        nsIURI *aUrl, 
+                                        uint32_t aChromeMask,
+                                        int32_t aInitialWidth,
+                                        int32_t aInitialHeight,
+                                        nsITabParent *aOpeningTab,
+                                        mozIDOMWindowProxy *aOpenerWindow,
+                                        nsIXULWindow **aResult)
+
+{
+  nsresult rv;
+
+  StartupTimeline::RecordOnce(StartupTimeline::CREATE_TOP_LEVEL_WINDOW);
+
+  RefPtr<nsWebShellWindow> newWindow;
+  rv = JustCreateTopWindow(aParent, aUrl,
+                           aChromeMask, aInitialWidth, aInitialHeight,
+                           false, aOpeningTab, aOpenerWindow,
+                           getter_AddRefs(newWindow));
+  newWindow.forget(aResult);
+
+  if (NS_SUCCEEDED(rv)) {
+    // the addref resulting from this is the owning addref for this window
+    RegisterTopLevelWindow(*aResult);
+    nsCOMPtr<nsIXULWindow> parent;
+    if (aChromeMask & nsIWebBrowserChrome::CHROME_DEPENDENT)
+      parent = aParent;
+    (*aResult)->SetZLevel(CalculateWindowZLevel(parent, aChromeMask));
+  }
+
+  return rv;
+}
+
+/*
+ * This class provides a stub implementation of nsIWebBrowserChrome2, as needed
+ * by nsAppShellService::CreateWindowlessBrowser
+ */
+class WebBrowserChrome2Stub : public nsIWebBrowserChrome2,
+                              public nsIEmbeddingSiteWindow,
+                              public nsIInterfaceRequestor,
+                              public nsSupportsWeakReference {
+protected:
+    virtual ~WebBrowserChrome2Stub() {}
+public:
+    NS_DECL_ISUPPORTS
+    NS_DECL_NSIWEBBROWSERCHROME
+    NS_DECL_NSIWEBBROWSERCHROME2
+    NS_DECL_NSIINTERFACEREQUESTOR
+    NS_DECL_NSIEMBEDDINGSITEWINDOW
+};
+
+NS_INTERFACE_MAP_BEGIN(WebBrowserChrome2Stub)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIWebBrowserChrome)
+  NS_INTERFACE_MAP_ENTRY(nsIWebBrowserChrome)
+  NS_INTERFACE_MAP_ENTRY(nsIWebBrowserChrome2)
+  NS_INTERFACE_MAP_ENTRY(nsIInterfaceRequestor)
+  NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
+  NS_INTERFACE_MAP_ENTRY(nsIEmbeddingSiteWindow)
+NS_INTERFACE_MAP_END
+
+NS_IMPL_ADDREF(WebBrowserChrome2Stub)
+NS_IMPL_RELEASE(WebBrowserChrome2Stub)
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::SetStatus(uint32_t aStatusType, const char16_t* aStatus)
+{
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::GetWebBrowser(nsIWebBrowser** aWebBrowser)
+{
+  NS_NOTREACHED("WebBrowserChrome2Stub::GetWebBrowser is not supported");
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::SetWebBrowser(nsIWebBrowser* aWebBrowser)
+{
+  NS_NOTREACHED("WebBrowserChrome2Stub::SetWebBrowser is not supported");
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::GetChromeFlags(uint32_t* aChromeFlags)
+{
+  *aChromeFlags = 0;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::SetChromeFlags(uint32_t aChromeFlags)
+{
+  NS_NOTREACHED("WebBrowserChrome2Stub::SetChromeFlags is not supported");
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::DestroyBrowserWindow()
+{
+  NS_NOTREACHED("WebBrowserChrome2Stub::DestroyBrowserWindow is not supported");
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::SizeBrowserTo(int32_t aCX, int32_t aCY)
+{
+  NS_NOTREACHED("WebBrowserChrome2Stub::SizeBrowserTo is not supported");
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::ShowAsModal()
+{
+  NS_NOTREACHED("WebBrowserChrome2Stub::ShowAsModal is not supported");
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::IsWindowModal(bool* aResult)
+{
+  *aResult = false;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::ExitModalEventLoop(nsresult aStatus)
+{
+  NS_NOTREACHED("WebBrowserChrome2Stub::ExitModalEventLoop is not supported");
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::SetStatusWithContext(uint32_t aStatusType,
+                                            const nsAString& aStatusText,
+                                            nsISupports* aStatusContext)
+{
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::GetInterface(const nsIID& aIID, void** aSink)
+{
+    return QueryInterface(aIID, aSink);
+}
+
+// nsIEmbeddingSiteWindow impl
+NS_IMETHODIMP
+WebBrowserChrome2Stub::GetDimensions(uint32_t flags, int32_t* x, int32_t* y, int32_t* cx, int32_t* cy)
+{
+  if (x) {
+    *x = 0;
+  }
+
+  if (y) {
+    *y = 0;
+  }
+
+  if (cx) {
+    *cx = 0;
+  }
+
+  if (cy) {
+    *cy = 0;
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::SetDimensions(uint32_t flags, int32_t x, int32_t y, int32_t cx, int32_t cy)
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::SetFocus()
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::GetVisibility(bool* aVisibility)
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+NS_IMETHODIMP
+WebBrowserChrome2Stub::SetVisibility(bool aVisibility)
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::GetTitle(char16_t** aTitle)
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+NS_IMETHODIMP
+WebBrowserChrome2Stub::SetTitle(const char16_t* aTitle)
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::GetSiteWindow(void** aSiteWindow)
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP
+WebBrowserChrome2Stub::Blur()
+{
+  return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+class BrowserDestroyer final : public Runnable
+{
+public:
+  BrowserDestroyer(nsIWebBrowser *aBrowser, nsISupports *aContainer) :
+    mBrowser(aBrowser),
+    mContainer(aContainer)
+  {
+  }
+
+  NS_IMETHOD
+  Run() override
+  {
+    // Explicitly destroy the browser, in case this isn't the last reference.
+    nsCOMPtr<nsIBaseWindow> window = do_QueryInterface(mBrowser);
+    return window->Destroy();
+  }
+
+protected:
+  virtual ~BrowserDestroyer() {}
+
+private:
+  nsCOMPtr<nsIWebBrowser> mBrowser;
+  nsCOMPtr<nsISupports> mContainer;
+};
+
+// This is the "stub" we return from CreateWindowlessBrowser - it exists
+// to manage the lifetimes of the nsIWebBrowser and container window.
+// In particular, it keeps a strong reference to both, to prevent them from
+// being collected while this object remains alive, and ensures that they
+// aren't destroyed when it's not safe to run scripts.
+class WindowlessBrowser final : public nsIWindowlessBrowser,
+                                public nsIInterfaceRequestor
+{
+public:
+  WindowlessBrowser(nsIWebBrowser *aBrowser, nsISupports *aContainer) :
+    mBrowser(aBrowser),
+    mContainer(aContainer),
+    mClosed(false)
+  {
+    mWebNavigation = do_QueryInterface(aBrowser);
+    mInterfaceRequestor = do_QueryInterface(aBrowser);
+  }
+  NS_DECL_ISUPPORTS
+  NS_FORWARD_SAFE_NSIWEBNAVIGATION(mWebNavigation)
+  NS_FORWARD_SAFE_NSIINTERFACEREQUESTOR(mInterfaceRequestor)
+
+  NS_IMETHOD
+  Close() override
+  {
+    NS_ENSURE_TRUE(!mClosed, NS_ERROR_UNEXPECTED);
+    NS_ASSERTION(nsContentUtils::IsSafeToRunScript(),
+                 "WindowlessBrowser::Close called when not safe to run scripts");
+
+    mClosed = true;
+
+    mWebNavigation = nullptr;
+    mInterfaceRequestor = nullptr;
+
+    nsCOMPtr<nsIBaseWindow> window = do_QueryInterface(mBrowser);
+    return window->Destroy();
+  }
+
+protected:
+  virtual ~WindowlessBrowser()
+  {
+    if (mClosed) {
+      return;
+    }
+
+    NS_WARNING("Windowless browser was not closed prior to destruction");
+
+    // The docshell destructor needs to dispatch events, and can only run
+    // when it's safe to run scripts. If this was triggered by GC, it may
+    // not always be safe to run scripts, in which cases we need to delay
+    // destruction until it is.
+    nsCOMPtr<nsIRunnable> runnable = new BrowserDestroyer(mBrowser, mContainer);
+    nsContentUtils::AddScriptRunner(runnable);
+  }
+
+private:
+  nsCOMPtr<nsIWebBrowser> mBrowser;
+  nsCOMPtr<nsIWebNavigation> mWebNavigation;
+  nsCOMPtr<nsIInterfaceRequestor> mInterfaceRequestor;
+  // we don't use the container but just hold a reference to it.
+  nsCOMPtr<nsISupports> mContainer;
+
+  bool mClosed;
+};
+
+NS_IMPL_ISUPPORTS(WindowlessBrowser, nsIWindowlessBrowser, nsIWebNavigation, nsIInterfaceRequestor)
+
+
+NS_IMETHODIMP
+nsAppShellService::CreateWindowlessBrowser(bool aIsChrome, nsIWindowlessBrowser **aResult)
+{
+  /* First, we create an instance of nsWebBrowser. Instances of this class have
+   * an associated doc shell, which is what we're interested in.
+   */
+  nsCOMPtr<nsIWebBrowser> browser = do_CreateInstance(NS_WEBBROWSER_CONTRACTID);
+  if (!browser) {
+    NS_ERROR("Couldn't create instance of nsWebBrowser!");
+    return NS_ERROR_FAILURE;
+  }
+
+  /* Next, we set the container window for our instance of nsWebBrowser. Since
+   * we don't actually have a window, we instead set the container window to be
+   * an instance of WebBrowserChrome2Stub, which provides a stub implementation
+   * of nsIWebBrowserChrome2.
+   */
+  RefPtr<WebBrowserChrome2Stub> stub = new WebBrowserChrome2Stub();
+  browser->SetContainerWindow(stub);
+
+  nsCOMPtr<nsIWebNavigation> navigation = do_QueryInterface(browser);
+
+  nsCOMPtr<nsIDocShellTreeItem> item = do_QueryInterface(navigation);
+  item->SetItemType(aIsChrome ? nsIDocShellTreeItem::typeChromeWrapper
+                              : nsIDocShellTreeItem::typeContentWrapper);
+
+  /* A windowless web browser doesn't have an associated OS level window. To
+   * accomplish this, we initialize the window associated with our instance of
+   * nsWebBrowser with an instance of PuppetWidget, which provides a stub
+   * implementation of nsIWidget.
+   */
+  nsCOMPtr<nsIWidget> widget = nsIWidget::CreatePuppetWidget(nullptr);
+  if (!widget) {
+    NS_ERROR("Couldn't create instance of PuppetWidget");
+    return NS_ERROR_FAILURE;
+  }
+  nsresult rv =
+    widget->Create(nullptr, 0, LayoutDeviceIntRect(0, 0, 0, 0), nullptr);
+  NS_ENSURE_SUCCESS(rv, rv);
+  nsCOMPtr<nsIBaseWindow> window = do_QueryInterface(navigation);
+  window->InitWindow(0, widget, 0, 0, 0, 0);
+  window->Create();
+
+  nsISupports *isstub = NS_ISUPPORTS_CAST(nsIWebBrowserChrome2*, stub);
+  RefPtr<nsIWindowlessBrowser> result = new WindowlessBrowser(browser, isstub);
+  nsCOMPtr<nsIDocShell> docshell = do_GetInterface(result);
+  docshell->SetInvisible(true);
+
+  result.forget(aResult);
+  return NS_OK;
+}
+
+uint32_t
+nsAppShellService::CalculateWindowZLevel(nsIXULWindow *aParent,
+                                         uint32_t      aChromeMask)
+{
+  uint32_t zLevel;
+
+  zLevel = nsIXULWindow::normalZ;
+  if (aChromeMask & nsIWebBrowserChrome::CHROME_WINDOW_RAISED)
+    zLevel = nsIXULWindow::raisedZ;
+  else if (aChromeMask & nsIWebBrowserChrome::CHROME_WINDOW_LOWERED)
+    zLevel = nsIXULWindow::loweredZ;
+
+#ifdef XP_MACOSX
+  /* Platforms on which modal windows are always application-modal, not
+     window-modal (that's just the Mac, right?) want modal windows to
+     be stacked on top of everyone else.
+
+     On Mac OS X, bind modality to parent window instead of app (ala Mac OS 9)
+  */
+  uint32_t modalDepMask = nsIWebBrowserChrome::CHROME_MODAL |
+                          nsIWebBrowserChrome::CHROME_DEPENDENT;
+  if (aParent && (aChromeMask & modalDepMask)) {
+    aParent->GetZLevel(&zLevel);
+  }
+#else
+  /* Platforms with native support for dependent windows (that's everyone
+      but pre-Mac OS X, right?) know how to stack dependent windows. On these
+      platforms, give the dependent window the same level as its parent,
+      so we won't try to override the normal platform behaviour. */
+  if ((aChromeMask & nsIWebBrowserChrome::CHROME_DEPENDENT) && aParent)
+    aParent->GetZLevel(&zLevel);
+#endif
+
+  return zLevel;
+}
+
+#ifdef XP_WIN
+/*
+ * Checks to see if any existing window is currently in fullscreen mode.
+ */
+static bool
+CheckForFullscreenWindow()
+{
+  nsCOMPtr<nsIWindowMediator> wm(do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+  if (!wm)
+    return false;
+
+  nsCOMPtr<nsISimpleEnumerator> windowList;
+  wm->GetXULWindowEnumerator(nullptr, getter_AddRefs(windowList));
+  if (!windowList)
+    return false;
+
+  for (;;) {
+    bool more = false;
+    windowList->HasMoreElements(&more);
+    if (!more)
+      return false;
+
+    nsCOMPtr<nsISupports> supportsWindow;
+    windowList->GetNext(getter_AddRefs(supportsWindow));
+    nsCOMPtr<nsIBaseWindow> baseWin(do_QueryInterface(supportsWindow));
+    if (baseWin) {
+      nsCOMPtr<nsIWidget> widget;
+      baseWin->GetMainWidget(getter_AddRefs(widget));
+      if (widget && widget->SizeMode() == nsSizeMode_Fullscreen) {
+        return true;
+      }
+    }
+  }
+  return false;
+}
+#endif
+
+/*
+ * Just do the window-making part of CreateTopLevelWindow
+ */
+nsresult
+nsAppShellService::JustCreateTopWindow(nsIXULWindow *aParent,
+                                       nsIURI *aUrl,
+                                       uint32_t aChromeMask,
+                                       int32_t aInitialWidth,
+                                       int32_t aInitialHeight,
+                                       bool aIsHiddenWindow,
+                                       nsITabParent *aOpeningTab,
+                                       mozIDOMWindowProxy *aOpenerWindow,
+                                       nsWebShellWindow **aResult)
+{
+  *aResult = nullptr;
+  NS_ENSURE_STATE(!mXPCOMWillShutDown);
+
+  nsCOMPtr<nsIXULWindow> parent;
+  if (aChromeMask & nsIWebBrowserChrome::CHROME_DEPENDENT)
+    parent = aParent;
+
+  RefPtr<nsWebShellWindow> window = new nsWebShellWindow(aChromeMask);
+
+#ifdef XP_WIN
+  // If the parent is currently fullscreen, tell the child to ignore persisted
+  // full screen states. This way new browser windows open on top of fullscreen
+  // windows normally.
+  if (window && CheckForFullscreenWindow())
+    window->IgnoreXULSizeMode(true);
+#endif
+
+  nsWidgetInitData widgetInitData;
+
+  if (aIsHiddenWindow)
+    widgetInitData.mWindowType = eWindowType_invisible;
+  else
+    widgetInitData.mWindowType = aChromeMask & nsIWebBrowserChrome::CHROME_OPENAS_DIALOG ?
+      eWindowType_dialog : eWindowType_toplevel;
+
+  if (aChromeMask & nsIWebBrowserChrome::CHROME_WINDOW_POPUP)
+    widgetInitData.mWindowType = eWindowType_popup;
+
+  if (aChromeMask & nsIWebBrowserChrome::CHROME_MAC_SUPPRESS_ANIMATION)
+    widgetInitData.mIsAnimationSuppressed = true;
+
+#ifdef XP_MACOSX
+  // Mac OS X sheet support
+  // Adding CHROME_OPENAS_CHROME to sheetMask makes modal windows opened from
+  // nsGlobalWindow::ShowModalDialog() be dialogs (not sheets), while modal
+  // windows opened from nsPromptService::DoDialog() still are sheets.  This
+  // fixes bmo bug 395465 (see nsCocoaWindow::StandardCreate() and
+  // nsCocoaWindow::SetModal()).
+  uint32_t sheetMask = nsIWebBrowserChrome::CHROME_OPENAS_DIALOG |
+                       nsIWebBrowserChrome::CHROME_MODAL |
+                       nsIWebBrowserChrome::CHROME_OPENAS_CHROME;
+  if (parent &&
+      (parent != mHiddenWindow && parent != mHiddenPrivateWindow) &&
+      ((aChromeMask & sheetMask) == sheetMask)) {
+    widgetInitData.mWindowType = eWindowType_sheet;
+  }
+#endif
+
+#if defined(XP_WIN)
+  if (widgetInitData.mWindowType == eWindowType_toplevel ||
+      widgetInitData.mWindowType == eWindowType_dialog)
+    widgetInitData.clipChildren = true;
+#endif
+
+  // note default chrome overrides other OS chrome settings, but
+  // not internal chrome
+  if (aChromeMask & nsIWebBrowserChrome::CHROME_DEFAULT)
+    widgetInitData.mBorderStyle = eBorderStyle_default;
+  else if ((aChromeMask & nsIWebBrowserChrome::CHROME_ALL) == nsIWebBrowserChrome::CHROME_ALL)
+    widgetInitData.mBorderStyle = eBorderStyle_all;
+  else {
+    widgetInitData.mBorderStyle = eBorderStyle_none; // assumes none == 0x00
+    if (aChromeMask & nsIWebBrowserChrome::CHROME_WINDOW_BORDERS)
+      widgetInitData.mBorderStyle = static_cast<enum nsBorderStyle>(widgetInitData.mBorderStyle | eBorderStyle_border);
+    if (aChromeMask & nsIWebBrowserChrome::CHROME_TITLEBAR)
+      widgetInitData.mBorderStyle = static_cast<enum nsBorderStyle>(widgetInitData.mBorderStyle | eBorderStyle_title);
+    if (aChromeMask & nsIWebBrowserChrome::CHROME_WINDOW_CLOSE)
+      widgetInitData.mBorderStyle = static_cast<enum nsBorderStyle>(widgetInitData.mBorderStyle | eBorderStyle_close);
+    if (aChromeMask & nsIWebBrowserChrome::CHROME_WINDOW_RESIZE) {
+      widgetInitData.mBorderStyle = static_cast<enum nsBorderStyle>(widgetInitData.mBorderStyle | eBorderStyle_resizeh);
+      // only resizable windows get the maximize button (but not dialogs)
+      if (!(aChromeMask & nsIWebBrowserChrome::CHROME_OPENAS_DIALOG))
+        widgetInitData.mBorderStyle = static_cast<enum nsBorderStyle>(widgetInitData.mBorderStyle | eBorderStyle_maximize);
+    }
+    // all windows (except dialogs) get minimize buttons and the system menu
+    if (!(aChromeMask & nsIWebBrowserChrome::CHROME_OPENAS_DIALOG))
+      widgetInitData.mBorderStyle = static_cast<enum nsBorderStyle>(widgetInitData.mBorderStyle | eBorderStyle_minimize | eBorderStyle_menu);
+    // but anyone can explicitly ask for a minimize button
+    if (aChromeMask & nsIWebBrowserChrome::CHROME_WINDOW_MIN) {
+      widgetInitData.mBorderStyle = static_cast<enum nsBorderStyle>(widgetInitData.mBorderStyle | eBorderStyle_minimize);
+    }  
+  }
+
+  if (aInitialWidth == nsIAppShellService::SIZE_TO_CONTENT ||
+      aInitialHeight == nsIAppShellService::SIZE_TO_CONTENT) {
+    aInitialWidth = 1;
+    aInitialHeight = 1;
+    window->SetIntrinsicallySized(true);
+  }
+
+  bool center = aChromeMask & nsIWebBrowserChrome::CHROME_CENTER_SCREEN;
+
+  nsCOMPtr<nsIXULChromeRegistry> reg =
+    mozilla::services::GetXULChromeRegistryService();
+  if (reg) {
+    nsAutoCString package;
+    package.AssignLiteral("global");
+    bool isRTL = false;
+    reg->IsLocaleRTL(package, &isRTL);
+    widgetInitData.mRTL = isRTL;
+  }
+
+#ifdef MOZ_WIDGET_GONK
+  // B2G multi-screen support. Screen ID is for differentiating screens of
+  // windows, and due to the hardware limitation, it is platform-specific for
+  // now, which align with the value of display type defined in HWC.
+  widgetInitData.mScreenId = mScreenId;
+#endif
+
+  nsresult rv = window->Initialize(parent, center ? aParent : nullptr,
+                                   aUrl, aInitialWidth, aInitialHeight,
+                                   aIsHiddenWindow, aOpeningTab,
+                                   aOpenerWindow, widgetInitData);
+
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  // Enforce the Private Browsing autoStart pref first.
+  bool isPrivateBrowsingWindow =
+    Preferences::GetBool("browser.privatebrowsing.autostart");
+  bool isUsingRemoteTabs = mozilla::BrowserTabsRemoteAutostart();
+
+  if (aChromeMask & nsIWebBrowserChrome::CHROME_PRIVATE_WINDOW) {
+    // Caller requested a private window
+    isPrivateBrowsingWindow = true;
+  }
+  if (aChromeMask & nsIWebBrowserChrome::CHROME_REMOTE_WINDOW) {
+    isUsingRemoteTabs = true;
+  }
+
+  nsCOMPtr<mozIDOMWindowProxy> domWin = do_GetInterface(aParent);
+  nsCOMPtr<nsIWebNavigation> webNav = do_GetInterface(domWin);
+  nsCOMPtr<nsILoadContext> parentContext = do_QueryInterface(webNav);
+
+  if (!isPrivateBrowsingWindow && parentContext) {
+    // Ensure that we propagate any existing private browsing status
+    // from the parent, even if it will not actually be used
+    // as a parent value.
+    isPrivateBrowsingWindow = parentContext->UsePrivateBrowsing();
+  }
+
+  if (parentContext) {
+    isUsingRemoteTabs = parentContext->UseRemoteTabs();
+  }
+
+  nsCOMPtr<mozIDOMWindowProxy> newDomWin =
+      do_GetInterface(NS_ISUPPORTS_CAST(nsIBaseWindow*, window));
+  nsCOMPtr<nsIWebNavigation> newWebNav = do_GetInterface(newDomWin);
+  nsCOMPtr<nsILoadContext> thisContext = do_GetInterface(newWebNav);
+  if (thisContext) {
+    thisContext->SetPrivateBrowsing(isPrivateBrowsingWindow);
+    thisContext->SetRemoteTabs(isUsingRemoteTabs);
+  }
+
+  window.forget(aResult);
+  if (parent)
+    parent->AddChildWindow(*aResult);
+
+  if (center)
+    rv = (*aResult)->Center(parent, parent ? false : true, false);
+
+  return rv;
+}
+
+NS_IMETHODIMP
+nsAppShellService::GetHiddenWindow(nsIXULWindow **aWindow)
+{
+  NS_ENSURE_ARG_POINTER(aWindow);
+
+  *aWindow = mHiddenWindow;
+  NS_IF_ADDREF(*aWindow);
+  return *aWindow ? NS_OK : NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+nsAppShellService::GetHiddenDOMWindow(mozIDOMWindowProxy **aWindow)
+{
+  nsresult rv;
+  nsCOMPtr<nsIDocShell> docShell;
+  NS_ENSURE_TRUE(mHiddenWindow, NS_ERROR_FAILURE);
+
+  rv = mHiddenWindow->GetDocShell(getter_AddRefs(docShell));
+  NS_ENSURE_SUCCESS(rv, rv);
+  NS_ENSURE_TRUE(docShell, NS_ERROR_FAILURE);
+
+  nsCOMPtr<nsPIDOMWindowOuter> hiddenDOMWindow(docShell->GetWindow());
+  hiddenDOMWindow.forget(aWindow);
+  return *aWindow ? NS_OK : NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+nsAppShellService::GetHiddenPrivateWindow(nsIXULWindow **aWindow)
+{
+  NS_ENSURE_ARG_POINTER(aWindow);
+
+  EnsurePrivateHiddenWindow();
+
+  *aWindow = mHiddenPrivateWindow;
+  NS_IF_ADDREF(*aWindow);
+  return *aWindow ? NS_OK : NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+nsAppShellService::GetHiddenPrivateDOMWindow(mozIDOMWindowProxy **aWindow)
+{
+  EnsurePrivateHiddenWindow();
+
+  nsresult rv;
+  nsCOMPtr<nsIDocShell> docShell;
+  NS_ENSURE_TRUE(mHiddenPrivateWindow, NS_ERROR_FAILURE);
+
+  rv = mHiddenPrivateWindow->GetDocShell(getter_AddRefs(docShell));
+  NS_ENSURE_SUCCESS(rv, rv);
+  NS_ENSURE_TRUE(docShell, NS_ERROR_FAILURE);
+
+  nsCOMPtr<nsPIDOMWindowOuter> hiddenPrivateDOMWindow(docShell->GetWindow());
+  hiddenPrivateDOMWindow.forget(aWindow);
+  return *aWindow ? NS_OK : NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP
+nsAppShellService::GetHasHiddenPrivateWindow(bool* aHasPrivateWindow)
+{
+  NS_ENSURE_ARG_POINTER(aHasPrivateWindow);
+
+  *aHasPrivateWindow = !!mHiddenPrivateWindow;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppShellService::GetApplicationProvidedHiddenWindow(bool* aAPHW)
+{
+    *aAPHW = mApplicationProvidedHiddenWindow;
+    return NS_OK;
+}
+
+/*
+ * Register a new top level window (created elsewhere)
+ */
+NS_IMETHODIMP
+nsAppShellService::RegisterTopLevelWindow(nsIXULWindow* aWindow)
+{
+  NS_ENSURE_ARG_POINTER(aWindow);
+
+  nsCOMPtr<nsIDocShell> docShell;
+  aWindow->GetDocShell(getter_AddRefs(docShell));
+  NS_ENSURE_TRUE(docShell, NS_ERROR_FAILURE);
+
+  nsCOMPtr<nsPIDOMWindowOuter> domWindow(docShell->GetWindow());
+  NS_ENSURE_TRUE(domWindow, NS_ERROR_FAILURE);
+  domWindow->SetInitialPrincipalToSubject();
+
+  // tell the window mediator about the new window
+  nsCOMPtr<nsIWindowMediator> mediator
+    ( do_GetService(NS_WINDOWMEDIATOR_CONTRACTID) );
+  NS_ASSERTION(mediator, "Couldn't get window mediator.");
+
+  if (mediator)
+    mediator->RegisterWindow(aWindow);
+
+  // tell the window watcher about the new window
+  nsCOMPtr<nsPIWindowWatcher> wwatcher ( do_GetService(NS_WINDOWWATCHER_CONTRACTID) );
+  NS_ASSERTION(wwatcher, "No windowwatcher?");
+  if (wwatcher && domWindow) {
+    wwatcher->AddWindow(domWindow, 0);
+  }
+
+  // an ongoing attempt to quit is stopped by a newly opened window
+  nsCOMPtr<nsIObserverService> obssvc = services::GetObserverService();
+  NS_ASSERTION(obssvc, "Couldn't get observer service.");
+
+  if (obssvc) {
+    obssvc->NotifyObservers(aWindow, "xul-window-registered", nullptr);
+    nsXULWindow* xulWindow = static_cast<nsXULWindow*>(aWindow);
+    xulWindow->WasRegistered();
+  }
+
+  return NS_OK;
+}
+
+
+NS_IMETHODIMP
+nsAppShellService::UnregisterTopLevelWindow(nsIXULWindow* aWindow)
+{
+  if (mXPCOMShuttingDown) {
+    /* return an error code in order to:
+       - avoid doing anything with other member variables while we are in
+         the destructor
+       - notify the caller not to release the AppShellService after
+         unregistering the window
+         (we don't want to be deleted twice consecutively to
+         mHiddenWindow->Destroy() in our destructor)
+    */
+    return NS_ERROR_FAILURE;
+  }
+
+  NS_ENSURE_ARG_POINTER(aWindow);
+
+  if (aWindow == mHiddenWindow) {
+    // CreateHiddenWindow() does not register the window, so we're done.
+    return NS_OK;
+  }
+  if (aWindow == mHiddenPrivateWindow) {
+    // CreateHiddenWindow() does not register the window, so we're done.
+    return NS_OK;
+  }
+
+  // tell the window mediator
+  nsCOMPtr<nsIWindowMediator> mediator
+    ( do_GetService(NS_WINDOWMEDIATOR_CONTRACTID) );
+  NS_ASSERTION(mediator, "Couldn't get window mediator. Doing xpcom shutdown?");
+
+  if (mediator)
+    mediator->UnregisterWindow(aWindow);
+
+  // tell the window watcher
+  nsCOMPtr<nsPIWindowWatcher> wwatcher ( do_GetService(NS_WINDOWWATCHER_CONTRACTID) );
+  NS_ASSERTION(wwatcher, "Couldn't get windowwatcher, doing xpcom shutdown?");
+  if (wwatcher) {
+    nsCOMPtr<nsIDocShell> docShell;
+    aWindow->GetDocShell(getter_AddRefs(docShell));
+    if (docShell) {
+      nsCOMPtr<nsPIDOMWindowOuter> domWindow(docShell->GetWindow());
+      if (domWindow)
+        wwatcher->RemoveWindow(domWindow);
+    }
+  }
+
+  return NS_OK;
+}
+
+
+NS_IMETHODIMP
+nsAppShellService::Observe(nsISupports* aSubject, const char *aTopic,
+                           const char16_t *aData)
+{
+  if (!strcmp(aTopic, "xpcom-will-shutdown")) {
+    mXPCOMWillShutDown = true;
+  } else if (!strcmp(aTopic, "xpcom-shutdown")) {
+    mXPCOMShuttingDown = true;
+    if (mHiddenWindow) {
+      mHiddenWindow->Destroy();
+    }
+    if (mHiddenPrivateWindow) {
+      mHiddenPrivateWindow->Destroy();
+    }
+  } else {
+    NS_ERROR("Unexpected observer topic!");
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppShellService::StartEventLoopLagTracking(bool* aResult)
+{
+#ifdef MOZ_INSTRUMENT_EVENT_LOOP
+    *aResult = mozilla::InitEventTracing(true);
+#endif
+    return NS_OK;
+}
+
+NS_IMETHODIMP
+nsAppShellService::StopEventLoopLagTracking()
+{
+#ifdef MOZ_INSTRUMENT_EVENT_LOOP
+    mozilla::ShutdownEventTracing();
+#endif
+    return NS_OK;
+}
diff --git a/xpfe/appshell/nsAppShellService.h b/xpfe/appshell/nsAppShellService.h
new file mode 100644
index 000000000..feb7b9947
--- /dev/null
+++ b/xpfe/appshell/nsAppShellService.h
@@ -0,0 +1,58 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef __nsAppShellService_h
+#define __nsAppShellService_h
+
+#include "nsIAppShellService.h"
+#include "nsIObserver.h"
+
+//Interfaces Needed
+#include "nsWebShellWindow.h"
+#include "nsStringFwd.h"
+#include "nsAutoPtr.h"
+#include "nsITabParent.h"
+#include "mozilla/Attributes.h"
+
+// {0099907D-123C-4853-A46A-43098B5FB68C}
+#define NS_APPSHELLSERVICE_CID \
+{ 0x99907d, 0x123c, 0x4853, { 0xa4, 0x6a, 0x43, 0x9, 0x8b, 0x5f, 0xb6, 0x8c } }
+
+class nsAppShellService final : public nsIAppShellService,
+                                public nsIObserver
+{
+public:
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIAPPSHELLSERVICE
+  NS_DECL_NSIOBSERVER
+
+  nsAppShellService();
+
+protected:
+  ~nsAppShellService();
+
+  nsresult CreateHiddenWindowHelper(bool aIsPrivate);
+  void EnsurePrivateHiddenWindow();
+
+  nsresult JustCreateTopWindow(nsIXULWindow *aParent,
+                               nsIURI *aUrl,
+                               uint32_t aChromeMask,
+                               int32_t aInitialWidth, int32_t aInitialHeight,
+                               bool aIsHiddenWindow,
+                               nsITabParent *aOpeningTab,
+                               mozIDOMWindowProxy *aOpenerWindow,
+                               nsWebShellWindow **aResult);
+  uint32_t CalculateWindowZLevel(nsIXULWindow *aParent, uint32_t aChromeMask);
+
+  RefPtr<nsWebShellWindow>  mHiddenWindow;
+  RefPtr<nsWebShellWindow>  mHiddenPrivateWindow;
+  bool                        mXPCOMWillShutDown;
+  bool                        mXPCOMShuttingDown;
+  uint16_t                    mModalWindowCount;
+  bool                        mApplicationProvidedHiddenWindow;
+  uint32_t                    mScreenId;
+};
+
+#endif
diff --git a/xpfe/appshell/nsAppShellWindowEnumerator.cpp b/xpfe/appshell/nsAppShellWindowEnumerator.cpp
new file mode 100644
index 000000000..dc5fc120a
--- /dev/null
+++ b/xpfe/appshell/nsAppShellWindowEnumerator.cpp
@@ -0,0 +1,495 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsAppShellWindowEnumerator.h"
+
+#include "nsIContentViewer.h"
+#include "nsIDocShell.h"
+#include "nsIDocument.h"
+#include "nsIDOMDocument.h"
+#include "nsIDOMElement.h"
+#include "nsIDOMWindow.h"
+#include "nsIFactory.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsIXULWindow.h"
+
+#include "nsWindowMediator.h"
+
+//
+// static helper functions
+//
+
+static nsCOMPtr<nsIDOMNode> GetDOMNodeFromDocShell(nsIDocShell *aShell);
+static void GetAttribute(nsIXULWindow *inWindow, const nsAString &inAttribute,
+                         nsAString &outValue);
+static void GetWindowType(nsIXULWindow* inWindow, nsString &outType);
+
+nsCOMPtr<nsIDOMNode> GetDOMNodeFromDocShell(nsIDocShell *aShell)
+{
+  nsCOMPtr<nsIDOMNode> node;
+
+  nsCOMPtr<nsIContentViewer> cv;
+  aShell->GetContentViewer(getter_AddRefs(cv));
+  if (cv) {
+    nsCOMPtr<nsIDOMDocument> domdoc(do_QueryInterface(cv->GetDocument()));
+    if (domdoc) {
+      nsCOMPtr<nsIDOMElement> element;
+      domdoc->GetDocumentElement(getter_AddRefs(element));
+      if (element)
+        node = element;
+    }
+  }
+
+  return node;
+}
+
+// generic "retrieve the value of a XUL attribute" function
+void GetAttribute(nsIXULWindow *inWindow, const nsAString &inAttribute,
+                  nsAString &outValue)
+{
+  nsCOMPtr<nsIDocShell> shell;
+  if (inWindow && NS_SUCCEEDED(inWindow->GetDocShell(getter_AddRefs(shell)))) {
+    nsCOMPtr<nsIDOMNode> node(GetDOMNodeFromDocShell(shell));
+    if (node) {
+      nsCOMPtr<nsIDOMElement> webshellElement(do_QueryInterface(node));
+      if (webshellElement)
+        webshellElement->GetAttribute(inAttribute, outValue);
+    }
+  }
+}
+
+// retrieve the window type, stored as the value of a particular
+// attribute in its XUL window tag
+void GetWindowType(nsIXULWindow* aWindow, nsString &outType)
+{
+  GetAttribute(aWindow, NS_LITERAL_STRING("windowtype"), outType);
+}
+
+//
+// nsWindowInfo
+//
+
+nsWindowInfo::nsWindowInfo(nsIXULWindow* inWindow, int32_t inTimeStamp) :
+  mWindow(inWindow),mTimeStamp(inTimeStamp),mZLevel(nsIXULWindow::normalZ)
+{
+  ReferenceSelf(true, true);
+}
+
+nsWindowInfo::~nsWindowInfo()
+{
+}
+
+// return true if the window described by this WindowInfo has a type
+// equal to the given type
+bool nsWindowInfo::TypeEquals(const nsAString &aType)
+{ 
+  nsAutoString rtnString;
+  GetWindowType(mWindow, rtnString);
+  return rtnString == aType;
+}
+
+// insert the struct into their two linked lists, in position after the
+// given (independent) method arguments
+void nsWindowInfo::InsertAfter(nsWindowInfo *inOlder , nsWindowInfo *inHigher)
+{
+  if (inOlder) {
+    mOlder = inOlder;
+    mYounger = inOlder->mYounger;
+    mOlder->mYounger = this;
+    if (mOlder->mOlder == mOlder)
+      mOlder->mOlder = this;
+    mYounger->mOlder = this;
+    if (mYounger->mYounger == mYounger)
+      mYounger->mYounger = this;
+  }
+  if (inHigher) {
+    mHigher = inHigher;
+    mLower = inHigher->mLower;
+    mHigher->mLower = this;
+    if (mHigher->mHigher == mHigher)
+      mHigher->mHigher = this;
+    mLower->mHigher = this;
+    if (mLower->mLower == mLower)
+      mLower->mLower = this;
+  }
+}
+
+// remove the struct from its linked lists
+void nsWindowInfo::Unlink(bool inAge, bool inZ)
+{
+  if (inAge) {
+    mOlder->mYounger = mYounger;
+    mYounger->mOlder = mOlder;
+  }
+  if (inZ) {
+    mLower->mHigher = mHigher;
+    mHigher->mLower = mLower;
+  }
+  ReferenceSelf(inAge, inZ);
+}
+
+// initialize the struct to be a valid linked list of one element
+void nsWindowInfo::ReferenceSelf(bool inAge, bool inZ)
+{
+  if (inAge) {
+    mYounger = this;
+    mOlder = this;
+  }
+  if (inZ) {
+    mLower = this;
+    mHigher = this;
+  }
+}
+
+//
+// nsAppShellWindowEnumerator
+//
+
+NS_IMPL_ISUPPORTS(nsAppShellWindowEnumerator, nsISimpleEnumerator)
+
+nsAppShellWindowEnumerator::nsAppShellWindowEnumerator(
+    const char16_t* aTypeString,
+    nsWindowMediator& aMediator) :
+      mWindowMediator(&aMediator), mType(aTypeString), mCurrentPosition(nullptr)
+{
+  mWindowMediator->AddEnumerator(this);
+  NS_ADDREF(mWindowMediator);
+}
+
+nsAppShellWindowEnumerator::~nsAppShellWindowEnumerator()
+{
+  mWindowMediator->RemoveEnumerator(this);
+  NS_RELEASE(mWindowMediator);
+}
+
+// after mCurrentPosition has been initialized to point to the beginning
+// of the appropriate list, adjust it if necessary
+void nsAppShellWindowEnumerator::AdjustInitialPosition()
+{
+  if (!mType.IsEmpty() && mCurrentPosition && !mCurrentPosition->TypeEquals(mType))
+    mCurrentPosition = FindNext();
+}
+
+NS_IMETHODIMP nsAppShellWindowEnumerator::HasMoreElements(bool *retval)
+{
+  if (!retval)
+    return NS_ERROR_INVALID_ARG;
+
+  *retval = mCurrentPosition ? true : false;
+  return NS_OK;
+}
+
+// if a window is being removed adjust the iterator's current position
+void nsAppShellWindowEnumerator::WindowRemoved(nsWindowInfo *inInfo)
+{
+  if (mCurrentPosition == inInfo)
+    mCurrentPosition = FindNext();
+}
+
+//
+// nsASDOMWindowEnumerator
+//
+
+nsASDOMWindowEnumerator::nsASDOMWindowEnumerator(
+    const char16_t* aTypeString,
+    nsWindowMediator& aMediator) :
+      nsAppShellWindowEnumerator(aTypeString, aMediator)
+{
+}
+
+nsASDOMWindowEnumerator::~nsASDOMWindowEnumerator()
+{
+}
+
+NS_IMETHODIMP nsASDOMWindowEnumerator::GetNext(nsISupports **retval)
+{
+  if (!retval)
+    return NS_ERROR_INVALID_ARG;
+
+  *retval = nullptr;
+  while (mCurrentPosition) {
+    nsCOMPtr<nsPIDOMWindowOuter> domWindow;
+    nsWindowMediator::GetDOMWindow(mCurrentPosition->mWindow, domWindow);
+    mCurrentPosition = FindNext();
+    if (domWindow)
+      return CallQueryInterface(domWindow, retval);
+  }
+  return NS_OK;
+}
+
+//
+// nsASXULWindowEnumerator
+//
+
+nsASXULWindowEnumerator::nsASXULWindowEnumerator(
+    const char16_t* aTypeString,
+    nsWindowMediator& aMediator) :
+      nsAppShellWindowEnumerator(aTypeString, aMediator)
+{
+}
+
+nsASXULWindowEnumerator::~nsASXULWindowEnumerator()
+{
+}
+
+NS_IMETHODIMP nsASXULWindowEnumerator::GetNext(nsISupports **retval)
+{
+  if (!retval)
+    return NS_ERROR_INVALID_ARG;
+
+  *retval = nullptr;
+  if (mCurrentPosition) {
+    CallQueryInterface(mCurrentPosition->mWindow, retval);
+    mCurrentPosition = FindNext();
+  }
+  return NS_OK;
+}
+
+//
+// nsASDOMWindowEarlyToLateEnumerator
+//
+
+nsASDOMWindowEarlyToLateEnumerator::nsASDOMWindowEarlyToLateEnumerator(
+    const char16_t *aTypeString,
+    nsWindowMediator &aMediator) :
+      nsASDOMWindowEnumerator(aTypeString, aMediator)
+{
+  mCurrentPosition = aMediator.mOldestWindow;
+  AdjustInitialPosition();
+}
+
+nsASDOMWindowEarlyToLateEnumerator::~nsASDOMWindowEarlyToLateEnumerator()
+{
+}
+
+nsWindowInfo *nsASDOMWindowEarlyToLateEnumerator::FindNext()
+{
+  nsWindowInfo *info,
+               *listEnd;
+  bool          allWindows = mType.IsEmpty();
+
+  // see nsXULWindowEarlyToLateEnumerator::FindNext
+  if (!mCurrentPosition)
+    return nullptr;
+
+  info = mCurrentPosition->mYounger;
+  listEnd = mWindowMediator->mOldestWindow;
+
+  while (info != listEnd) {
+    if (allWindows || info->TypeEquals(mType))
+      return info;
+    info = info->mYounger;
+  }
+
+  return nullptr;
+}
+
+//
+// nsASXULWindowEarlyToLateEnumerator
+//
+
+nsASXULWindowEarlyToLateEnumerator::nsASXULWindowEarlyToLateEnumerator(
+    const char16_t *aTypeString,
+    nsWindowMediator &aMediator) :
+      nsASXULWindowEnumerator(aTypeString, aMediator)
+{
+  mCurrentPosition = aMediator.mOldestWindow;
+  AdjustInitialPosition();
+}
+
+nsASXULWindowEarlyToLateEnumerator::~nsASXULWindowEarlyToLateEnumerator()
+{
+}
+
+nsWindowInfo *nsASXULWindowEarlyToLateEnumerator::FindNext()
+{
+  nsWindowInfo *info,
+               *listEnd;
+  bool          allWindows = mType.IsEmpty();
+
+  /* mCurrentPosition null is assumed to mean that the enumerator has run
+     its course and is now basically useless. It could also be interpreted
+     to mean that it was created at a time when there were no windows. In
+     that case it would probably be more appropriate to check to see whether
+     windows have subsequently been added. But it's not guaranteed that we'll
+     pick up newly added windows anyway (if they occurred previous to our
+     current position) so we just don't worry about that. */
+  if (!mCurrentPosition)
+    return nullptr;
+
+  info = mCurrentPosition->mYounger;
+  listEnd = mWindowMediator->mOldestWindow;
+
+  while (info != listEnd) {
+    if (allWindows || info->TypeEquals(mType))
+      return info;
+    info = info->mYounger;
+  }
+
+  return nullptr;
+}
+
+//
+// nsASDOMWindowFrontToBackEnumerator
+//
+
+nsASDOMWindowFrontToBackEnumerator::nsASDOMWindowFrontToBackEnumerator(
+    const char16_t *aTypeString,
+    nsWindowMediator &aMediator) :
+      nsASDOMWindowEnumerator(aTypeString, aMediator)
+{
+  mCurrentPosition = aMediator.mTopmostWindow;
+  AdjustInitialPosition();
+}
+
+nsASDOMWindowFrontToBackEnumerator::~nsASDOMWindowFrontToBackEnumerator()
+{
+}
+
+nsWindowInfo *nsASDOMWindowFrontToBackEnumerator::FindNext()
+{
+  nsWindowInfo *info,
+               *listEnd;
+  bool          allWindows = mType.IsEmpty();
+
+  // see nsXULWindowEarlyToLateEnumerator::FindNext
+  if (!mCurrentPosition)
+    return nullptr;
+
+  info = mCurrentPosition->mLower;
+  listEnd = mWindowMediator->mTopmostWindow;
+
+  while (info != listEnd) {
+    if (allWindows || info->TypeEquals(mType))
+      return info;
+    info = info->mLower;
+  }
+
+  return nullptr;
+}
+
+//
+// nsASXULWindowFrontToBackEnumerator
+//
+
+nsASXULWindowFrontToBackEnumerator::nsASXULWindowFrontToBackEnumerator(
+    const char16_t *aTypeString,
+    nsWindowMediator &aMediator) :
+      nsASXULWindowEnumerator(aTypeString, aMediator)
+{
+  mCurrentPosition = aMediator.mTopmostWindow;
+  AdjustInitialPosition();
+}
+
+nsASXULWindowFrontToBackEnumerator::~nsASXULWindowFrontToBackEnumerator()
+{
+}
+
+nsWindowInfo *nsASXULWindowFrontToBackEnumerator::FindNext()
+{
+  nsWindowInfo *info,
+               *listEnd;
+  bool          allWindows = mType.IsEmpty();
+
+  // see nsXULWindowEarlyToLateEnumerator::FindNext
+  if (!mCurrentPosition)
+    return nullptr;
+
+  info = mCurrentPosition->mLower;
+  listEnd = mWindowMediator->mTopmostWindow;
+
+  while (info != listEnd) {
+    if (allWindows || info->TypeEquals(mType))
+      return info;
+    info = info->mLower;
+  }
+
+  return nullptr;
+}
+
+//
+// nsASDOMWindowBackToFrontEnumerator
+//
+
+nsASDOMWindowBackToFrontEnumerator::nsASDOMWindowBackToFrontEnumerator(
+    const char16_t *aTypeString,
+    nsWindowMediator &aMediator) :
+  nsASDOMWindowEnumerator(aTypeString, aMediator)
+{
+  mCurrentPosition = aMediator.mTopmostWindow ?
+                     aMediator.mTopmostWindow->mHigher : nullptr;
+  AdjustInitialPosition();
+}
+
+nsASDOMWindowBackToFrontEnumerator::~nsASDOMWindowBackToFrontEnumerator()
+{
+}
+
+nsWindowInfo *nsASDOMWindowBackToFrontEnumerator::FindNext()
+{
+  nsWindowInfo *info,
+               *listEnd;
+  bool          allWindows = mType.IsEmpty();
+
+  // see nsXULWindowEarlyToLateEnumerator::FindNext
+  if (!mCurrentPosition)
+    return nullptr;
+
+  info = mCurrentPosition->mHigher;
+  listEnd = mWindowMediator->mTopmostWindow;
+  if (listEnd)
+    listEnd = listEnd->mHigher;
+
+  while (info != listEnd) {
+    if (allWindows || info->TypeEquals(mType))
+      return info;
+    info = info->mHigher;
+  }
+
+  return nullptr;
+}
+
+//
+// nsASXULWindowBackToFrontEnumerator
+//
+
+nsASXULWindowBackToFrontEnumerator::nsASXULWindowBackToFrontEnumerator(
+    const char16_t *aTypeString,
+    nsWindowMediator &aMediator) :
+      nsASXULWindowEnumerator(aTypeString, aMediator)
+{
+  mCurrentPosition = aMediator.mTopmostWindow ?
+                     aMediator.mTopmostWindow->mHigher : nullptr;
+  AdjustInitialPosition();
+}
+
+nsASXULWindowBackToFrontEnumerator::~nsASXULWindowBackToFrontEnumerator()
+{
+}
+
+nsWindowInfo *nsASXULWindowBackToFrontEnumerator::FindNext()
+{
+  nsWindowInfo *info,
+               *listEnd;
+  bool          allWindows = mType.IsEmpty();
+
+  // see nsXULWindowEarlyToLateEnumerator::FindNext
+  if (!mCurrentPosition)
+    return nullptr;
+
+  info = mCurrentPosition->mHigher;
+  listEnd = mWindowMediator->mTopmostWindow;
+  if (listEnd)
+    listEnd = listEnd->mHigher;
+
+  while (info != listEnd) {
+    if (allWindows || info->TypeEquals(mType))
+      return info;
+    info = info->mHigher;
+  }
+
+  return nullptr;
+}
diff --git a/xpfe/appshell/nsAppShellWindowEnumerator.h b/xpfe/appshell/nsAppShellWindowEnumerator.h
new file mode 100644
index 000000000..f9a8a2d52
--- /dev/null
+++ b/xpfe/appshell/nsAppShellWindowEnumerator.h
@@ -0,0 +1,166 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsAppShellWindowEnumerator_h
+#define nsAppShellWindowEnumerator_h
+
+#include "nsCOMPtr.h"
+#include "nsString.h"
+
+#include "nsISimpleEnumerator.h"
+#include "nsIXULWindow.h"
+
+class nsWindowMediator;
+
+//
+// nsWindowInfo
+//
+
+struct nsWindowInfo
+{
+  nsWindowInfo(nsIXULWindow* inWindow, int32_t inTimeStamp);
+  ~nsWindowInfo();
+
+  nsCOMPtr<nsIXULWindow>    mWindow;
+  int32_t                   mTimeStamp;
+  uint32_t                  mZLevel;
+
+  // each struct is in two, independent, circular, doubly-linked lists
+  nsWindowInfo              *mYounger, // next younger in sequence
+                            *mOlder;
+  nsWindowInfo              *mLower,   // next lower in z-order
+                            *mHigher;
+  
+  bool TypeEquals(const nsAString &aType);
+  void   InsertAfter(nsWindowInfo *inOlder, nsWindowInfo *inHigher);
+  void   Unlink(bool inAge, bool inZ);
+  void   ReferenceSelf(bool inAge, bool inZ);
+};
+
+//
+// virtual enumerators
+//
+
+class nsAppShellWindowEnumerator : public nsISimpleEnumerator {
+
+friend class nsWindowMediator;
+
+public:
+  nsAppShellWindowEnumerator(const char16_t* aTypeString,
+                             nsWindowMediator& inMediator);
+  NS_IMETHOD GetNext(nsISupports **retval) override = 0;
+  NS_IMETHOD HasMoreElements(bool *retval) override;
+
+  NS_DECL_ISUPPORTS
+
+protected:
+
+  virtual ~nsAppShellWindowEnumerator();
+
+  void AdjustInitialPosition();
+  virtual nsWindowInfo *FindNext() = 0;
+
+  void WindowRemoved(nsWindowInfo *inInfo);
+
+  nsWindowMediator *mWindowMediator;
+  nsString          mType;
+  nsWindowInfo     *mCurrentPosition;
+};
+
+class nsASDOMWindowEnumerator : public nsAppShellWindowEnumerator {
+
+public:
+  nsASDOMWindowEnumerator(const char16_t* aTypeString,
+                          nsWindowMediator& inMediator);
+  virtual ~nsASDOMWindowEnumerator();
+  NS_IMETHOD GetNext(nsISupports **retval);
+};
+
+class nsASXULWindowEnumerator : public nsAppShellWindowEnumerator {
+
+public:
+  nsASXULWindowEnumerator(const char16_t* aTypeString,
+                          nsWindowMediator& inMediator);
+  virtual ~nsASXULWindowEnumerator();
+  NS_IMETHOD GetNext(nsISupports **retval);
+};
+
+//
+// concrete enumerators
+//
+
+class nsASDOMWindowEarlyToLateEnumerator : public nsASDOMWindowEnumerator {
+
+public:
+  nsASDOMWindowEarlyToLateEnumerator(const char16_t* aTypeString,
+                                     nsWindowMediator& inMediator);
+
+  virtual ~nsASDOMWindowEarlyToLateEnumerator();
+
+protected:
+  virtual nsWindowInfo *FindNext();
+};
+
+class nsASXULWindowEarlyToLateEnumerator : public nsASXULWindowEnumerator {
+
+public:
+  nsASXULWindowEarlyToLateEnumerator(const char16_t* aTypeString,
+                                     nsWindowMediator& inMediator);
+
+  virtual ~nsASXULWindowEarlyToLateEnumerator();
+
+protected:
+  virtual nsWindowInfo *FindNext();
+};
+
+class nsASDOMWindowFrontToBackEnumerator : public nsASDOMWindowEnumerator {
+
+public:
+  nsASDOMWindowFrontToBackEnumerator(const char16_t* aTypeString,
+                                     nsWindowMediator& inMediator);
+
+  virtual ~nsASDOMWindowFrontToBackEnumerator();
+
+protected:
+  virtual nsWindowInfo *FindNext();
+};
+
+class nsASXULWindowFrontToBackEnumerator : public nsASXULWindowEnumerator {
+
+public:
+  nsASXULWindowFrontToBackEnumerator(const char16_t* aTypeString,
+                                     nsWindowMediator& inMediator);
+
+  virtual ~nsASXULWindowFrontToBackEnumerator();
+
+protected:
+  virtual nsWindowInfo *FindNext();
+};
+
+class nsASDOMWindowBackToFrontEnumerator : public nsASDOMWindowEnumerator {
+
+public:
+  nsASDOMWindowBackToFrontEnumerator(const char16_t* aTypeString,
+                                     nsWindowMediator& inMediator);
+
+  virtual ~nsASDOMWindowBackToFrontEnumerator();
+
+protected:
+  virtual nsWindowInfo *FindNext();
+};
+
+class nsASXULWindowBackToFrontEnumerator : public nsASXULWindowEnumerator {
+
+public:
+  nsASXULWindowBackToFrontEnumerator(const char16_t* aTypeString,
+                                     nsWindowMediator& inMediator);
+
+  virtual ~nsASXULWindowBackToFrontEnumerator();
+
+protected:
+  virtual nsWindowInfo *FindNext();
+};
+
+#endif
diff --git a/xpfe/appshell/nsChromeTreeOwner.cpp b/xpfe/appshell/nsChromeTreeOwner.cpp
new file mode 100644
index 000000000..63fa86373
--- /dev/null
+++ b/xpfe/appshell/nsChromeTreeOwner.cpp
@@ -0,0 +1,561 @@
+/* -*- Mode: C++; tab-width: 3; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Local Includes
+#include "nsChromeTreeOwner.h"
+#include "nsXULWindow.h"
+
+// Helper Classes
+#include "nsString.h"
+#include "nsIEmbeddingSiteWindow.h"
+#include "nsIServiceManager.h"
+#include "nsIDocShellTreeItem.h"
+
+// Interfaces needed to include
+#include "nsIPrompt.h"
+#include "nsIAuthPrompt.h"
+#include "nsIBrowserDOMWindow.h"
+#include "nsIWebProgress.h"
+#include "nsIWidget.h"
+#include "nsIWindowMediator.h"
+#include "nsIDOMChromeWindow.h"
+#include "nsIDOMNode.h"
+#include "nsIDOMElement.h"
+#include "nsIDOMNodeList.h"
+#include "nsIDOMXULElement.h"
+#include "nsIXULBrowserWindow.h"
+#include "mozilla/dom/Element.h"
+
+using namespace mozilla;
+
+//*****************************************************************************
+// nsChromeTreeOwner string literals
+//*****************************************************************************
+
+struct nsChromeTreeOwnerLiterals
+{
+  const nsLiteralString kPersist;
+  const nsLiteralString kScreenX;
+  const nsLiteralString kScreenY;
+  const nsLiteralString kWidth;
+  const nsLiteralString kHeight;
+  const nsLiteralString kSizemode;
+  const nsLiteralString kSpace;
+
+  nsChromeTreeOwnerLiterals()
+    : NS_LITERAL_STRING_INIT(kPersist,"persist")
+    , NS_LITERAL_STRING_INIT(kScreenX,"screenX")
+    , NS_LITERAL_STRING_INIT(kScreenY,"screenY")
+    , NS_LITERAL_STRING_INIT(kWidth,"width")
+    , NS_LITERAL_STRING_INIT(kHeight,"height")
+    , NS_LITERAL_STRING_INIT(kSizemode,"sizemode")
+    , NS_LITERAL_STRING_INIT(kSpace," ")
+  {}
+};
+
+static nsChromeTreeOwnerLiterals *gLiterals;
+
+nsresult
+nsChromeTreeOwner::InitGlobals()
+{
+  NS_ASSERTION(gLiterals == nullptr, "already initialized");
+  gLiterals = new nsChromeTreeOwnerLiterals();
+  return NS_OK;
+}
+
+void
+nsChromeTreeOwner::FreeGlobals()
+{
+  delete gLiterals;
+  gLiterals = nullptr;
+}
+
+//*****************************************************************************
+//***    nsChromeTreeOwner: Object Management
+//*****************************************************************************
+
+nsChromeTreeOwner::nsChromeTreeOwner() : mXULWindow(nullptr)
+{
+}
+
+nsChromeTreeOwner::~nsChromeTreeOwner()
+{
+}
+
+//*****************************************************************************
+// nsChromeTreeOwner::nsISupports
+//*****************************************************************************   
+
+NS_IMPL_ADDREF(nsChromeTreeOwner)
+NS_IMPL_RELEASE(nsChromeTreeOwner)
+
+NS_INTERFACE_MAP_BEGIN(nsChromeTreeOwner)
+   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIDocShellTreeOwner)
+   NS_INTERFACE_MAP_ENTRY(nsIDocShellTreeOwner)
+   NS_INTERFACE_MAP_ENTRY(nsIBaseWindow)
+   NS_INTERFACE_MAP_ENTRY(nsIWebProgressListener)
+   NS_INTERFACE_MAP_ENTRY(nsIInterfaceRequestor)
+   NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
+NS_INTERFACE_MAP_END
+
+//*****************************************************************************
+// nsChromeTreeOwner::nsIInterfaceRequestor
+//*****************************************************************************   
+
+NS_IMETHODIMP nsChromeTreeOwner::GetInterface(const nsIID& aIID, void** aSink)
+{
+  NS_ENSURE_ARG_POINTER(aSink);
+
+  if(aIID.Equals(NS_GET_IID(nsIPrompt))) {
+    NS_ENSURE_STATE(mXULWindow);
+    return mXULWindow->GetInterface(aIID, aSink);
+  }
+  if(aIID.Equals(NS_GET_IID(nsIAuthPrompt))) {
+    NS_ENSURE_STATE(mXULWindow);
+    return mXULWindow->GetInterface(aIID, aSink);
+  }
+  if(aIID.Equals(NS_GET_IID(nsIWebBrowserChrome))) {
+    NS_ENSURE_STATE(mXULWindow);
+    return mXULWindow->GetInterface(aIID, aSink);
+  }
+  if (aIID.Equals(NS_GET_IID(nsIEmbeddingSiteWindow))) {
+    NS_ENSURE_STATE(mXULWindow);
+    return mXULWindow->GetInterface(aIID, aSink);
+  }
+  if (aIID.Equals(NS_GET_IID(nsIXULWindow))) {
+    NS_ENSURE_STATE(mXULWindow);
+    return mXULWindow->QueryInterface(aIID, aSink);
+  }
+
+  return QueryInterface(aIID, aSink);
+}
+
+//*****************************************************************************
+// nsChromeTreeOwner::nsIDocShellTreeOwner
+//*****************************************************************************   
+
+NS_IMETHODIMP
+nsChromeTreeOwner::ContentShellAdded(nsIDocShellTreeItem* aContentShell,
+                                     bool aPrimary, bool aTargetable,
+                                     const nsAString& aID)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->ContentShellAdded(aContentShell, aPrimary, aTargetable,
+                                       aID);
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::ContentShellRemoved(nsIDocShellTreeItem* aContentShell)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->ContentShellRemoved(aContentShell);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetPrimaryContentShell(nsIDocShellTreeItem** aShell)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetPrimaryContentShell(aShell);
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::TabParentAdded(nsITabParent* aTab, bool aPrimary)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->TabParentAdded(aTab, aPrimary);
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::TabParentRemoved(nsITabParent* aTab)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->TabParentRemoved(aTab);
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::GetPrimaryTabParent(nsITabParent** aTab)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->GetPrimaryTabParent(aTab);
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::GetPrimaryContentSize(int32_t* aWidth,
+                                         int32_t* aHeight)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->GetPrimaryContentSize(aWidth, aHeight);
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::SetPrimaryContentSize(int32_t aWidth,
+                                         int32_t aHeight)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->SetPrimaryContentSize(aWidth, aHeight);
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::GetRootShellSize(int32_t* aWidth,
+                                    int32_t* aHeight)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->GetRootShellSize(aWidth, aHeight);
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::SetRootShellSize(int32_t aWidth,
+                                    int32_t aHeight)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->SetRootShellSize(aWidth, aHeight);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SizeShellTo(nsIDocShellTreeItem* aShellItem,
+   int32_t aCX, int32_t aCY)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SizeShellTo(aShellItem, aCX, aCY);
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::SetPersistence(bool aPersistPosition,
+                                  bool aPersistSize,
+                                  bool aPersistSizeMode)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  nsCOMPtr<dom::Element> docShellElement = mXULWindow->GetWindowDOMElement();
+  if (!docShellElement)
+    return NS_ERROR_FAILURE;
+
+  nsAutoString persistString;
+  docShellElement->GetAttribute(gLiterals->kPersist, persistString);
+
+  bool saveString = false;
+  int32_t index;
+
+#define FIND_PERSIST_STRING(aString, aCond)            \
+  index = persistString.Find(aString);                 \
+  if (!aCond && index > kNotFound) {                   \
+    persistString.Cut(index, aString.Length());        \
+    saveString = true;                              \
+  } else if (aCond && index == kNotFound) {            \
+    persistString.Append(gLiterals->kSpace + aString); \
+    saveString = true;                              \
+  }
+  FIND_PERSIST_STRING(gLiterals->kScreenX,  aPersistPosition);
+  FIND_PERSIST_STRING(gLiterals->kScreenY,  aPersistPosition);
+  FIND_PERSIST_STRING(gLiterals->kWidth,    aPersistSize);
+  FIND_PERSIST_STRING(gLiterals->kHeight,   aPersistSize);
+  FIND_PERSIST_STRING(gLiterals->kSizemode, aPersistSizeMode);
+
+  ErrorResult rv;
+  if (saveString) {
+    docShellElement->SetAttribute(gLiterals->kPersist, persistString, rv);
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::GetPersistence(bool* aPersistPosition,
+                                  bool* aPersistSize,
+                                  bool* aPersistSizeMode)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  nsCOMPtr<dom::Element> docShellElement = mXULWindow->GetWindowDOMElement();
+  if (!docShellElement)
+    return NS_ERROR_FAILURE;
+
+  nsAutoString persistString;
+  docShellElement->GetAttribute(gLiterals->kPersist, persistString);
+
+  // data structure doesn't quite match the question, but it's close enough
+  // for what we want (since this method is never actually called...)
+  if (aPersistPosition)
+    *aPersistPosition = persistString.Find(gLiterals->kScreenX) > kNotFound ||
+                        persistString.Find(gLiterals->kScreenY) > kNotFound;
+  if (aPersistSize)
+    *aPersistSize = persistString.Find(gLiterals->kWidth) > kNotFound ||
+                    persistString.Find(gLiterals->kHeight) > kNotFound;
+  if (aPersistSizeMode)
+    *aPersistSizeMode = persistString.Find(gLiterals->kSizemode) > kNotFound;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::GetTargetableShellCount(uint32_t* aResult)
+{
+  *aResult = 0;
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::GetHasPrimaryContent(bool* aResult)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->GetHasPrimaryContent(aResult);
+}
+
+//*****************************************************************************
+// nsChromeTreeOwner::nsIBaseWindow
+//*****************************************************************************   
+
+NS_IMETHODIMP nsChromeTreeOwner::InitWindow(nativeWindow aParentNativeWindow,
+   nsIWidget* parentWidget, int32_t x, int32_t y, int32_t cx, int32_t cy)   
+{
+   // Ignore widget parents for now.  Don't think those are a vaild thing to call.
+   NS_ENSURE_SUCCESS(SetPositionAndSize(x, y, cx, cy, 0), NS_ERROR_FAILURE);
+
+   return NS_OK;
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::Create()
+{
+   NS_ASSERTION(false, "You can't call this");
+   return NS_ERROR_UNEXPECTED;
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::Destroy()
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->Destroy();
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetUnscaledDevicePixelsPerCSSPixel(double *aScale)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetUnscaledDevicePixelsPerCSSPixel(aScale);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetDevicePixelsPerDesktopPixel(double *aScale)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetDevicePixelsPerDesktopPixel(aScale);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SetPositionDesktopPix(int32_t x, int32_t y)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetPositionDesktopPix(x, y);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SetPosition(int32_t x, int32_t y)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetPosition(x, y);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetPosition(int32_t* x, int32_t* y)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetPosition(x, y);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SetSize(int32_t cx, int32_t cy, bool fRepaint)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetSize(cx, cy, fRepaint);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetSize(int32_t* cx, int32_t* cy)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetSize(cx, cy);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SetPositionAndSize(int32_t x, int32_t y, int32_t cx,
+   int32_t cy, uint32_t aFlags)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetPositionAndSize(x, y, cx, cy, aFlags);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetPositionAndSize(int32_t* x, int32_t* y, int32_t* cx,
+   int32_t* cy)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetPositionAndSize(x, y, cx, cy);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::Repaint(bool aForce)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->Repaint(aForce);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetParentWidget(nsIWidget** aParentWidget)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetParentWidget(aParentWidget);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SetParentWidget(nsIWidget* aParentWidget)
+{
+   NS_ASSERTION(false, "You can't call this");
+   return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetParentNativeWindow(nativeWindow* aParentNativeWindow)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetParentNativeWindow(aParentNativeWindow);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SetParentNativeWindow(nativeWindow aParentNativeWindow)
+{
+   NS_ASSERTION(false, "You can't call this");
+   return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetNativeHandle(nsAString& aNativeHandle)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetNativeHandle(aNativeHandle);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetVisibility(bool* aVisibility)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetVisibility(aVisibility);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SetVisibility(bool aVisibility)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetVisibility(aVisibility);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetEnabled(bool *aEnabled)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetEnabled(aEnabled);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SetEnabled(bool aEnable)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetEnabled(aEnable);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetMainWidget(nsIWidget** aMainWidget)
+{
+   NS_ENSURE_ARG_POINTER(aMainWidget);
+   NS_ENSURE_STATE(mXULWindow);
+
+   *aMainWidget = mXULWindow->mWindow;
+   NS_IF_ADDREF(*aMainWidget);
+
+   return NS_OK;
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SetFocus()
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetFocus();
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::GetTitle(char16_t** aTitle)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetTitle(aTitle);
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::SetTitle(const char16_t* aTitle)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetTitle(aTitle);
+}
+
+//*****************************************************************************
+// nsChromeTreeOwner::nsIWebProgressListener
+//*****************************************************************************   
+
+NS_IMETHODIMP
+nsChromeTreeOwner::OnProgressChange(nsIWebProgress* aWebProgress,
+                                    nsIRequest* aRequest,
+                                    int32_t aCurSelfProgress,
+                                    int32_t aMaxSelfProgress, 
+                                    int32_t aCurTotalProgress,
+                                    int32_t aMaxTotalProgress)
+{
+   return NS_OK;
+}
+
+NS_IMETHODIMP
+nsChromeTreeOwner::OnStateChange(nsIWebProgress* aWebProgress,
+                                 nsIRequest* aRequest,
+                                 uint32_t aProgressStateFlags,
+                                 nsresult aStatus)
+{
+   return NS_OK;
+}
+
+NS_IMETHODIMP nsChromeTreeOwner::OnLocationChange(nsIWebProgress* aWebProgress,
+                                                  nsIRequest* aRequest,
+                                                  nsIURI* aLocation,
+                                                  uint32_t aFlags)
+{
+  bool itsForYou = true;
+
+  if (aWebProgress) {
+    NS_ENSURE_STATE(mXULWindow);
+    nsCOMPtr<mozIDOMWindowProxy> progressWin;
+    aWebProgress->GetDOMWindow(getter_AddRefs(progressWin));
+
+    nsCOMPtr<nsIDocShell> docshell;
+    mXULWindow->GetDocShell(getter_AddRefs(docshell));
+    // XXXkhuey this is totally wrong, bug 1223303.
+    nsCOMPtr<mozIDOMWindowProxy> ourWin(do_QueryInterface(docshell));
+
+    if (ourWin != progressWin)
+      itsForYou = false;
+  }
+
+   // If loading a new root .xul document, then redo chrome.
+  if (itsForYou) {
+    NS_ENSURE_STATE(mXULWindow);
+    mXULWindow->mChromeLoaded = false;
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP 
+nsChromeTreeOwner::OnStatusChange(nsIWebProgress* aWebProgress,
+                                  nsIRequest* aRequest,
+                                  nsresult aStatus,
+                                  const char16_t* aMessage)
+{
+    return NS_OK;
+}
+
+
+
+NS_IMETHODIMP 
+nsChromeTreeOwner::OnSecurityChange(nsIWebProgress *aWebProgress, 
+                                    nsIRequest *aRequest, 
+                                    uint32_t state)
+{
+    return NS_OK;
+}
+
+//*****************************************************************************
+// nsChromeTreeOwner: Helpers
+//*****************************************************************************   
+
+//*****************************************************************************
+// nsChromeTreeOwner: Accessors
+//*****************************************************************************   
+
+void nsChromeTreeOwner::XULWindow(nsXULWindow* aXULWindow)
+{
+   mXULWindow = aXULWindow;
+}
+
+nsXULWindow* nsChromeTreeOwner::XULWindow()
+{
+   return mXULWindow;
+}
diff --git a/xpfe/appshell/nsChromeTreeOwner.h b/xpfe/appshell/nsChromeTreeOwner.h
new file mode 100644
index 000000000..77b0dea89
--- /dev/null
+++ b/xpfe/appshell/nsChromeTreeOwner.h
@@ -0,0 +1,53 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsChromeTreeOwner_h__
+#define nsChromeTreeOwner_h__
+
+// Helper Classes
+#include "nsCOMPtr.h"
+
+// Interfaces Needed
+#include "nsIBaseWindow.h"
+#include "nsIDocShellTreeOwner.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsIWebProgressListener.h"
+#include "nsWeakReference.h"
+
+class nsXULWindow;
+
+class nsChromeTreeOwner : public nsIDocShellTreeOwner,
+                          public nsIBaseWindow, 
+                          public nsIInterfaceRequestor,
+                          public nsIWebProgressListener,
+                          public nsSupportsWeakReference
+{
+friend class nsXULWindow;
+
+public:
+   NS_DECL_ISUPPORTS
+
+   NS_DECL_NSIINTERFACEREQUESTOR
+   NS_DECL_NSIBASEWINDOW
+   NS_DECL_NSIDOCSHELLTREEOWNER
+   NS_DECL_NSIWEBPROGRESSLISTENER
+
+   static nsresult InitGlobals();
+   static void     FreeGlobals();
+
+protected:
+   nsChromeTreeOwner();
+   virtual ~nsChromeTreeOwner();
+
+   void XULWindow(nsXULWindow* aXULWindow);
+   nsXULWindow* XULWindow();
+
+protected:
+   nsXULWindow*      mXULWindow;
+};
+
+#endif /* nsChromeTreeOwner_h__ */
diff --git a/xpfe/appshell/nsContentTreeOwner.cpp b/xpfe/appshell/nsContentTreeOwner.cpp
new file mode 100644
index 000000000..b39b7610f
--- /dev/null
+++ b/xpfe/appshell/nsContentTreeOwner.cpp
@@ -0,0 +1,1131 @@
+/* -*- Mode: C++; tab-width: 3; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ * vim: set ts=2 sw=2 et tw=79:
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+// Local Includes
+#include "nsContentTreeOwner.h"
+#include "nsXULWindow.h"
+
+// Helper Classes
+#include "nsIServiceManager.h"
+#include "nsAutoPtr.h"
+
+// Interfaces needed to be included
+#include "nsIDOMNode.h"
+#include "nsIDOMElement.h"
+#include "nsIDOMNodeList.h"
+#include "nsIDOMWindow.h"
+#include "nsIDOMChromeWindow.h"
+#include "nsIBrowserDOMWindow.h"
+#include "nsIDOMXULElement.h"
+#include "nsIEmbeddingSiteWindow.h"
+#include "nsIPrompt.h"
+#include "nsIAuthPrompt.h"
+#include "nsIWindowMediator.h"
+#include "nsIXULBrowserWindow.h"
+#include "nsIPrincipal.h"
+#include "nsIURIFixup.h"
+#include "nsCDefaultURIFixup.h"
+#include "nsIWebNavigation.h"
+#include "nsDocShellCID.h"
+#include "nsIExternalURLHandlerService.h"
+#include "nsIMIMEInfo.h"
+#include "nsIWidget.h"
+#include "nsWindowWatcher.h"
+#include "mozilla/BrowserElementParent.h"
+
+#include "nsIDOMDocument.h"
+#include "nsIScriptObjectPrincipal.h"
+#include "nsIURI.h"
+#include "nsIDocument.h"
+#if defined(XP_MACOSX)
+#include "nsThreadUtils.h"
+#endif
+
+#include "mozilla/Preferences.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/ScriptSettings.h"
+
+using namespace mozilla;
+
+//*****************************************************************************
+//*** nsSiteWindow declaration
+//*****************************************************************************
+
+class nsSiteWindow : public nsIEmbeddingSiteWindow
+{
+  // nsSiteWindow shares a lifetime with nsContentTreeOwner, and proxies it's
+  // AddRef and Release calls to said object.
+  // When nsContentTreeOwner is destroyed, nsSiteWindow will be destroyed as well.
+  // nsContentTreeOwner is a friend class of nsSiteWindow such that it can call
+  // nsSiteWindow's destructor, which is private, as public destructors
+  // on reference counted classes are generally unsafe.
+  friend class nsContentTreeOwner;
+
+public:
+  explicit nsSiteWindow(nsContentTreeOwner *aAggregator);
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_NSIEMBEDDINGSITEWINDOW
+
+private:
+  virtual ~nsSiteWindow();
+  nsContentTreeOwner *mAggregator;
+};
+
+//*****************************************************************************
+//***    nsContentTreeOwner: Object Management
+//*****************************************************************************
+
+nsContentTreeOwner::nsContentTreeOwner(bool fPrimary) : mXULWindow(nullptr), 
+   mPrimary(fPrimary), mContentTitleSetting(false)
+{
+  // note if this fails, QI on nsIEmbeddingSiteWindow(2) will simply fail
+  mSiteWindow = new nsSiteWindow(this);
+}
+
+nsContentTreeOwner::~nsContentTreeOwner()
+{
+  delete mSiteWindow;
+}
+
+//*****************************************************************************
+// nsContentTreeOwner::nsISupports
+//*****************************************************************************   
+
+NS_IMPL_ADDREF(nsContentTreeOwner)
+NS_IMPL_RELEASE(nsContentTreeOwner)
+
+NS_INTERFACE_MAP_BEGIN(nsContentTreeOwner)
+   NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIDocShellTreeOwner)
+   NS_INTERFACE_MAP_ENTRY(nsIDocShellTreeOwner)
+   NS_INTERFACE_MAP_ENTRY(nsIBaseWindow)
+   NS_INTERFACE_MAP_ENTRY(nsIWebBrowserChrome)
+   NS_INTERFACE_MAP_ENTRY(nsIWebBrowserChrome2)
+   NS_INTERFACE_MAP_ENTRY(nsIWebBrowserChrome3)
+   NS_INTERFACE_MAP_ENTRY(nsIInterfaceRequestor)
+   NS_INTERFACE_MAP_ENTRY(nsIWindowProvider)
+   // NOTE: This is using aggregation because there are some properties and
+   // method on nsIBaseWindow (which we implement) and on
+   // nsIEmbeddingSiteWindow (which we also implement) that have the same name.
+   // And it just so happens that we want different behavior for these methods
+   // and properties depending on the interface through which they're called
+   // (SetFocus() is a good example here).  If it were not for that, we could
+   // ditch the aggregation and just deal with not being able to use NS_DECL_*
+   // macros for this stuff....
+   NS_INTERFACE_MAP_ENTRY_AGGREGATED(nsIEmbeddingSiteWindow, mSiteWindow)
+NS_INTERFACE_MAP_END
+
+//*****************************************************************************
+// nsContentTreeOwner::nsIInterfaceRequestor
+//*****************************************************************************   
+
+NS_IMETHODIMP nsContentTreeOwner::GetInterface(const nsIID& aIID, void** aSink)
+{
+  NS_ENSURE_ARG_POINTER(aSink);
+  *aSink = 0;
+
+  if(aIID.Equals(NS_GET_IID(nsIPrompt))) {
+    NS_ENSURE_STATE(mXULWindow);
+    return mXULWindow->GetInterface(aIID, aSink);
+  }
+  if(aIID.Equals(NS_GET_IID(nsIAuthPrompt))) {
+    NS_ENSURE_STATE(mXULWindow);
+    return mXULWindow->GetInterface(aIID, aSink);
+  }
+  if (aIID.Equals(NS_GET_IID(nsIDocShellTreeItem))) {
+    NS_ENSURE_STATE(mXULWindow);
+    nsCOMPtr<nsIDocShell> shell;
+    mXULWindow->GetDocShell(getter_AddRefs(shell));
+    if (shell)
+      return shell->QueryInterface(aIID, aSink);
+    return NS_ERROR_FAILURE;
+  }
+
+  if (aIID.Equals(NS_GET_IID(nsIDOMWindow)) ||
+      aIID.Equals(NS_GET_IID(nsPIDOMWindowOuter))) {
+    NS_ENSURE_STATE(mXULWindow);
+    nsCOMPtr<nsIDocShellTreeItem> shell;
+    mXULWindow->GetPrimaryContentShell(getter_AddRefs(shell));
+    if (shell) {
+      nsCOMPtr<nsIInterfaceRequestor> thing(do_QueryInterface(shell));
+      if (thing)
+        return thing->GetInterface(aIID, aSink);
+    }
+    return NS_ERROR_FAILURE;
+  }
+
+  if (aIID.Equals(NS_GET_IID(nsIXULWindow))) {
+    NS_ENSURE_STATE(mXULWindow);
+    return mXULWindow->QueryInterface(aIID, aSink);
+  }
+
+  return QueryInterface(aIID, aSink);
+}
+
+//*****************************************************************************
+// nsContentTreeOwner::nsIDocShellTreeOwner
+//*****************************************************************************   
+
+NS_IMETHODIMP
+nsContentTreeOwner::ContentShellAdded(nsIDocShellTreeItem* aContentShell,
+                                      bool aPrimary, bool aTargetable,
+                                      const nsAString& aID)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->ContentShellAdded(aContentShell, aPrimary, aTargetable,
+                                       aID);
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::ContentShellRemoved(nsIDocShellTreeItem* aContentShell)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->ContentShellRemoved(aContentShell);
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::GetPrimaryContentShell(nsIDocShellTreeItem** aShell)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetPrimaryContentShell(aShell);
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::TabParentAdded(nsITabParent* aTab, bool aPrimary)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->TabParentAdded(aTab, aPrimary);
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::TabParentRemoved(nsITabParent* aTab)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->TabParentRemoved(aTab);
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::GetPrimaryTabParent(nsITabParent** aTab)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->GetPrimaryTabParent(aTab);
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::GetPrimaryContentSize(int32_t* aWidth,
+                                          int32_t* aHeight)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->GetPrimaryContentSize(aWidth, aHeight);
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::SetPrimaryContentSize(int32_t aWidth,
+                                          int32_t aHeight)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->SetPrimaryContentSize(aWidth, aHeight);
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::GetRootShellSize(int32_t* aWidth,
+                                     int32_t* aHeight)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->GetRootShellSize(aWidth, aHeight);
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::SetRootShellSize(int32_t aWidth,
+                                     int32_t aHeight)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->SetRootShellSize(aWidth, aHeight);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SizeShellTo(nsIDocShellTreeItem* aShellItem,
+   int32_t aCX, int32_t aCY)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SizeShellTo(aShellItem, aCX, aCY);
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::SetPersistence(bool aPersistPosition,
+                                   bool aPersistSize,
+                                   bool aPersistSizeMode)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  nsCOMPtr<dom::Element> docShellElement = mXULWindow->GetWindowDOMElement();
+  if (!docShellElement)
+    return NS_ERROR_FAILURE;
+
+  nsAutoString persistString;
+  docShellElement->GetAttribute(NS_LITERAL_STRING("persist"), persistString);
+
+  bool saveString = false;
+  int32_t index;
+
+  // Set X
+  index = persistString.Find("screenX");
+  if (!aPersistPosition && index >= 0) {
+    persistString.Cut(index, 7);
+    saveString = true;
+  } else if (aPersistPosition && index < 0) {
+    persistString.AppendLiteral(" screenX");
+    saveString = true;
+  }
+  // Set Y
+  index = persistString.Find("screenY");
+  if (!aPersistPosition && index >= 0) {
+    persistString.Cut(index, 7);
+    saveString = true;
+  } else if (aPersistPosition && index < 0) {
+    persistString.AppendLiteral(" screenY");
+    saveString = true;
+  }
+  // Set CX
+  index = persistString.Find("width");
+  if (!aPersistSize && index >= 0) {
+    persistString.Cut(index, 5);
+    saveString = true;
+  } else if (aPersistSize && index < 0) {
+    persistString.AppendLiteral(" width");
+    saveString = true;
+  }
+  // Set CY
+  index = persistString.Find("height");
+  if (!aPersistSize && index >= 0) {
+    persistString.Cut(index, 6);
+    saveString = true;
+  } else if (aPersistSize && index < 0) {
+    persistString.AppendLiteral(" height");
+    saveString = true;
+  }
+  // Set SizeMode
+  index = persistString.Find("sizemode");
+  if (!aPersistSizeMode && (index >= 0)) {
+    persistString.Cut(index, 8);
+    saveString = true;
+  } else if (aPersistSizeMode && (index < 0)) {
+    persistString.AppendLiteral(" sizemode");
+    saveString = true;
+  }
+
+  ErrorResult rv;
+  if(saveString) {
+    docShellElement->SetAttribute(NS_LITERAL_STRING("persist"), persistString, rv);
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::GetPersistence(bool* aPersistPosition,
+                                   bool* aPersistSize,
+                                   bool* aPersistSizeMode)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  nsCOMPtr<dom::Element> docShellElement = mXULWindow->GetWindowDOMElement();
+  if (!docShellElement)
+    return NS_ERROR_FAILURE;
+
+  nsAutoString persistString;
+  docShellElement->GetAttribute(NS_LITERAL_STRING("persist"), persistString);
+
+  // data structure doesn't quite match the question, but it's close enough
+  // for what we want (since this method is never actually called...)
+  if (aPersistPosition)
+    *aPersistPosition = persistString.Find("screenX") >= 0 || persistString.Find("screenY") >= 0 ? true : false;
+  if (aPersistSize)
+    *aPersistSize = persistString.Find("width") >= 0 || persistString.Find("height") >= 0 ? true : false;
+  if (aPersistSizeMode)
+    *aPersistSizeMode = persistString.Find("sizemode") >= 0 ? true : false;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::GetTargetableShellCount(uint32_t* aResult)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  *aResult = mXULWindow->mTargetableShells.Count();
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsContentTreeOwner::GetHasPrimaryContent(bool* aResult)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->GetHasPrimaryContent(aResult);
+}
+
+//*****************************************************************************
+// nsContentTreeOwner::nsIWebBrowserChrome3
+//*****************************************************************************   
+
+NS_IMETHODIMP nsContentTreeOwner::OnBeforeLinkTraversal(const nsAString &originalTarget,
+                                                        nsIURI *linkURI,
+                                                        nsIDOMNode *linkNode,
+                                                        bool isAppTab,
+                                                        nsAString &_retval)
+{
+  NS_ENSURE_STATE(mXULWindow);
+
+  nsCOMPtr<nsIXULBrowserWindow> xulBrowserWindow;
+  mXULWindow->GetXULBrowserWindow(getter_AddRefs(xulBrowserWindow));
+
+  if (xulBrowserWindow)
+    return xulBrowserWindow->OnBeforeLinkTraversal(originalTarget, linkURI,
+                                                   linkNode, isAppTab, _retval);
+  
+  _retval = originalTarget;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::ShouldLoadURI(nsIDocShell *aDocShell,
+                                                nsIURI *aURI,
+                                                nsIURI *aReferrer,
+                                                bool *_retval)
+{
+  NS_ENSURE_STATE(mXULWindow);
+
+  nsCOMPtr<nsIXULBrowserWindow> xulBrowserWindow;
+  mXULWindow->GetXULBrowserWindow(getter_AddRefs(xulBrowserWindow));
+
+  if (xulBrowserWindow)
+    return xulBrowserWindow->ShouldLoadURI(aDocShell, aURI, aReferrer, _retval);
+
+  *_retval = true;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::ReloadInFreshProcess(nsIDocShell* aDocShell,
+                                                       nsIURI* aURI,
+                                                       nsIURI* aReferrer,
+                                                       bool* aRetVal)
+{
+  NS_WARNING("Cannot reload in fresh process from a nsContentTreeOwner!");
+  *aRetVal = false;
+  return NS_OK;
+}
+
+//*****************************************************************************
+// nsContentTreeOwner::nsIWebBrowserChrome2
+//*****************************************************************************   
+
+NS_IMETHODIMP nsContentTreeOwner::SetStatusWithContext(uint32_t aStatusType,
+                                                       const nsAString &aStatusText,
+                                                       nsISupports *aStatusContext)
+{
+  // We only allow the status to be set from the primary content shell
+  if (!mPrimary && aStatusType != STATUS_LINK)
+    return NS_OK;
+
+  NS_ENSURE_STATE(mXULWindow);
+  
+  nsCOMPtr<nsIXULBrowserWindow> xulBrowserWindow;
+  mXULWindow->GetXULBrowserWindow(getter_AddRefs(xulBrowserWindow));
+
+  if (xulBrowserWindow)
+  {
+    switch(aStatusType)
+    {
+    case STATUS_SCRIPT:
+      xulBrowserWindow->SetJSStatus(aStatusText);
+      break;
+    case STATUS_LINK:
+      {
+        nsCOMPtr<nsIDOMElement> element = do_QueryInterface(aStatusContext);
+        xulBrowserWindow->SetOverLink(aStatusText, element);
+        break;
+      }
+    }
+  }
+
+  return NS_OK;
+}
+
+//*****************************************************************************
+// nsContentTreeOwner::nsIWebBrowserChrome
+//*****************************************************************************   
+
+NS_IMETHODIMP nsContentTreeOwner::SetStatus(uint32_t aStatusType,
+                                            const char16_t* aStatus)
+{
+  return SetStatusWithContext(aStatusType,
+      aStatus ? static_cast<const nsString &>(nsDependentString(aStatus))
+              : EmptyString(),
+      nullptr);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetWebBrowser(nsIWebBrowser* aWebBrowser)
+{
+   NS_ERROR("Haven't Implemented this yet");
+   return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetWebBrowser(nsIWebBrowser** aWebBrowser)
+{
+  // Unimplemented, and probably will remain so; xpfe windows have docshells,
+  // not webbrowsers.
+  NS_ENSURE_ARG_POINTER(aWebBrowser);
+  *aWebBrowser = 0;
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetChromeFlags(uint32_t aChromeFlags)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetChromeFlags(aChromeFlags);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetChromeFlags(uint32_t* aChromeFlags)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  return mXULWindow->GetChromeFlags(aChromeFlags);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::DestroyBrowserWindow()
+{
+   NS_ERROR("Haven't Implemented this yet");
+   return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SizeBrowserTo(int32_t aCX, int32_t aCY)
+{
+   NS_ERROR("Haven't Implemented this yet");
+   return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::ShowAsModal()
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->ShowModal();
+}
+
+NS_IMETHODIMP nsContentTreeOwner::IsWindowModal(bool *_retval)
+{
+  NS_ENSURE_STATE(mXULWindow);
+  *_retval = mXULWindow->mContinueModalLoop;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::ExitModalEventLoop(nsresult aStatus)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->ExitModalLoop(aStatus);   
+}
+
+//*****************************************************************************
+// nsContentTreeOwner::nsIBaseWindow
+//*****************************************************************************   
+
+NS_IMETHODIMP nsContentTreeOwner::InitWindow(nativeWindow aParentNativeWindow,
+   nsIWidget* parentWidget, int32_t x, int32_t y, int32_t cx, int32_t cy)   
+{
+   // Ignore wigdet parents for now.  Don't think those are a vaild thing to call.
+   NS_ENSURE_SUCCESS(SetPositionAndSize(x, y, cx, cy, 0), NS_ERROR_FAILURE);
+
+   return NS_OK;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::Create()
+{
+   NS_ASSERTION(false, "You can't call this");
+   return NS_ERROR_UNEXPECTED;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::Destroy()
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->Destroy();
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetUnscaledDevicePixelsPerCSSPixel(double* aScale)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetUnscaledDevicePixelsPerCSSPixel(aScale);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetDevicePixelsPerDesktopPixel(double* aScale)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetDevicePixelsPerDesktopPixel(aScale);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetPositionDesktopPix(int32_t aX, int32_t aY)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetPositionDesktopPix(aX, aY);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetPosition(int32_t aX, int32_t aY)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetPosition(aX, aY);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetPosition(int32_t* aX, int32_t* aY)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetPosition(aX, aY);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetSize(int32_t aCX, int32_t aCY, bool aRepaint)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetSize(aCX, aCY, aRepaint);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetSize(int32_t* aCX, int32_t* aCY)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetSize(aCX, aCY);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetPositionAndSize(int32_t aX, int32_t aY,
+   int32_t aCX, int32_t aCY, uint32_t aFlags)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetPositionAndSize(aX, aY, aCX, aCY, aFlags);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetPositionAndSize(int32_t* aX, int32_t* aY,
+   int32_t* aCX, int32_t* aCY)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetPositionAndSize(aX, aY, aCX, aCY); 
+}
+
+NS_IMETHODIMP nsContentTreeOwner::Repaint(bool aForce)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->Repaint(aForce);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetParentWidget(nsIWidget** aParentWidget)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetParentWidget(aParentWidget);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetParentWidget(nsIWidget* aParentWidget)
+{
+   NS_ASSERTION(false, "You can't call this");
+   return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetParentNativeWindow(nativeWindow* aParentNativeWindow)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetParentNativeWindow(aParentNativeWindow);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetParentNativeWindow(nativeWindow aParentNativeWindow)
+{
+   NS_ASSERTION(false, "You can't call this");
+   return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetNativeHandle(nsAString& aNativeHandle)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetNativeHandle(aNativeHandle);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetVisibility(bool* aVisibility)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetVisibility(aVisibility);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetVisibility(bool aVisibility)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetVisibility(aVisibility);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetEnabled(bool *aEnabled)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->GetEnabled(aEnabled);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetEnabled(bool aEnable)
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetEnabled(aEnable);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetMainWidget(nsIWidget** aMainWidget)
+{
+   NS_ENSURE_ARG_POINTER(aMainWidget);
+   NS_ENSURE_STATE(mXULWindow);
+
+   *aMainWidget = mXULWindow->mWindow;
+   NS_IF_ADDREF(*aMainWidget);
+
+   return NS_OK;
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetFocus()
+{
+   NS_ENSURE_STATE(mXULWindow);
+   return mXULWindow->SetFocus();
+}
+
+NS_IMETHODIMP nsContentTreeOwner::GetTitle(char16_t** aTitle)
+{
+   NS_ENSURE_ARG_POINTER(aTitle);
+   NS_ENSURE_STATE(mXULWindow);
+
+   return mXULWindow->GetTitle(aTitle);
+}
+
+NS_IMETHODIMP nsContentTreeOwner::SetTitle(const char16_t* aTitle)
+{
+   // We only allow the title to be set from the primary content shell
+  if(!mPrimary || !mContentTitleSetting)
+    return NS_OK;
+
+  NS_ENSURE_STATE(mXULWindow);
+  
+  nsAutoString   title;
+  nsAutoString   docTitle(aTitle);
+
+  if (docTitle.IsEmpty())
+    docTitle.Assign(mTitleDefault);
+
+  if (!docTitle.IsEmpty()) {
+    if (!mTitlePreface.IsEmpty()) {
+      // Title will be: "Preface: Doc Title - Mozilla"
+      title.Assign(mTitlePreface);
+      title.Append(docTitle);
+    }
+    else {
+      // Title will be: "Doc Title - Mozilla"
+      title = docTitle;
+    }
+
+    if (!mWindowTitleModifier.IsEmpty())
+      title += mTitleSeparator + mWindowTitleModifier;
+  }
+  else
+    title.Assign(mWindowTitleModifier); // Title will just be plain "Mozilla"
+
+  //
+  // if there is no location bar we modify the title to display at least
+  // the scheme and host (if any) as an anti-spoofing measure.
+  //
+  nsCOMPtr<dom::Element> docShellElement = mXULWindow->GetWindowDOMElement();
+
+  if (docShellElement) {
+    nsAutoString chromeString;
+    docShellElement->GetAttribute(NS_LITERAL_STRING("chromehidden"), chromeString);
+    if (chromeString.Find(NS_LITERAL_STRING("location")) != kNotFound) {
+      //
+      // location bar is turned off, find the browser location
+      //
+      // use the document's nsPrincipal to find the true owner
+      // in case of javascript: or data: documents
+      //
+      nsCOMPtr<nsIDocShellTreeItem> dsitem;
+      GetPrimaryContentShell(getter_AddRefs(dsitem));
+      nsCOMPtr<nsIScriptObjectPrincipal> doc =
+        do_QueryInterface(dsitem ? dsitem->GetDocument() : nullptr);
+      if (doc) {
+        nsCOMPtr<nsIURI> uri;
+        nsIPrincipal* principal = doc->GetPrincipal();
+        if (principal) {
+          principal->GetURI(getter_AddRefs(uri));
+          if (uri) {
+            //
+            // remove any user:pass information
+            //
+            nsCOMPtr<nsIURIFixup> fixup(do_GetService(NS_URIFIXUP_CONTRACTID));
+            if (fixup) {
+              nsCOMPtr<nsIURI> tmpuri;
+              nsresult rv = fixup->CreateExposableURI(uri,getter_AddRefs(tmpuri));
+              if (NS_SUCCEEDED(rv) && tmpuri) {
+                // (don't bother if there's no host)
+                nsAutoCString host;
+                nsAutoCString prepath;
+                tmpuri->GetHost(host);
+                tmpuri->GetPrePath(prepath);
+                if (!host.IsEmpty()) {
+                  //
+                  // We have a scheme/host, update the title
+                  //
+                  title.Insert(NS_ConvertUTF8toUTF16(prepath) +
+                               mTitleSeparator, 0);
+                }
+              }
+            }
+          }
+        }
+      }
+    }
+    nsIDocument* document = docShellElement->OwnerDoc();
+    ErrorResult rv;
+    document->SetTitle(title, rv);
+    return rv.StealNSResult();
+  }
+
+  return mXULWindow->SetTitle(title.get());
+}
+
+//*****************************************************************************
+// nsContentTreeOwner: nsIWindowProvider
+//*****************************************************************************   
+NS_IMETHODIMP
+nsContentTreeOwner::ProvideWindow(mozIDOMWindowProxy* aParent,
+                                  uint32_t aChromeFlags,
+                                  bool aCalledFromJS,
+                                  bool aPositionSpecified,
+                                  bool aSizeSpecified,
+                                  nsIURI* aURI,
+                                  const nsAString& aName,
+                                  const nsACString& aFeatures,
+                                  bool aForceNoOpener,
+                                  bool* aWindowIsNew,
+                                  mozIDOMWindowProxy** aReturn)
+{
+  NS_ENSURE_ARG_POINTER(aParent);
+
+  auto* parent = nsPIDOMWindowOuter::From(aParent);
+  
+  *aReturn = nullptr;
+
+  if (!mXULWindow) {
+    // Nothing to do here
+    return NS_OK;
+  }
+
+#ifdef DEBUG
+  nsCOMPtr<nsIWebNavigation> parentNav = do_GetInterface(aParent);
+  nsCOMPtr<nsIDocShellTreeOwner> parentOwner = do_GetInterface(parentNav);
+  NS_ASSERTION(SameCOMIdentity(parentOwner,
+                               static_cast<nsIDocShellTreeOwner*>(this)),
+               "Parent from wrong docshell tree?");
+#endif
+
+  // If aParent is inside an <iframe mozbrowser> and this isn't a request to
+  // open a modal-type window, we're going to create a new <iframe mozbrowser>
+  // and return its window here.
+  nsCOMPtr<nsIDocShell> docshell = do_GetInterface(aParent);
+  if (docshell && docshell->GetIsInMozBrowserOrApp() &&
+      !(aChromeFlags & (nsIWebBrowserChrome::CHROME_MODAL |
+                        nsIWebBrowserChrome::CHROME_OPENAS_DIALOG |
+                        nsIWebBrowserChrome::CHROME_OPENAS_CHROME))) {
+
+    BrowserElementParent::OpenWindowResult opened =
+      BrowserElementParent::OpenWindowInProcess(parent, aURI, aName,
+                                                aFeatures, aForceNoOpener, aReturn);
+
+    // If OpenWindowInProcess handled the open (by opening it or blocking the
+    // popup), tell our caller not to proceed trying to create a new window
+    // through other means.
+    if (opened != BrowserElementParent::OPEN_WINDOW_IGNORED) {
+      *aWindowIsNew = opened == BrowserElementParent::OPEN_WINDOW_ADDED;
+      return *aWindowIsNew ? NS_OK : NS_ERROR_ABORT;
+    }
+
+    // If we're in an app and the target is _blank, send the url to the OS
+    if (aName.LowerCaseEqualsLiteral("_blank")) {
+      nsCOMPtr<nsIExternalURLHandlerService> exUrlServ(
+                        do_GetService(NS_EXTERNALURLHANDLERSERVICE_CONTRACTID));
+      if (exUrlServ) {
+
+        nsCOMPtr<nsIHandlerInfo> info;
+        bool found;
+        exUrlServ->GetURLHandlerInfoFromOS(aURI, &found, getter_AddRefs(info));
+  
+        if (info && found) {
+          info->LaunchWithURI(aURI, nullptr);
+          return NS_ERROR_ABORT;
+        }
+
+      }
+    }
+  }
+
+  int32_t openLocation =
+    nsWindowWatcher::GetWindowOpenLocation(parent, aChromeFlags, aCalledFromJS,
+                                           aPositionSpecified, aSizeSpecified);
+
+  if (openLocation != nsIBrowserDOMWindow::OPEN_NEWTAB &&
+      openLocation != nsIBrowserDOMWindow::OPEN_CURRENTWINDOW) {
+    // Just open a window normally
+    return NS_OK;
+  }
+
+  nsCOMPtr<mozIDOMWindowProxy> domWin;
+  mXULWindow->GetWindowDOMWindow(getter_AddRefs(domWin));
+  nsCOMPtr<nsIDOMChromeWindow> chromeWin = do_QueryInterface(domWin);
+  if (!chromeWin) {
+    // Really odd... but whatever
+    NS_WARNING("nsXULWindow's DOMWindow is not a chrome window");
+    return NS_OK;
+  }
+
+  nsCOMPtr<nsIBrowserDOMWindow> browserDOMWin;
+  chromeWin->GetBrowserDOMWindow(getter_AddRefs(browserDOMWin));
+  if (!browserDOMWin) {
+    return NS_OK;
+  }
+
+  *aWindowIsNew = (openLocation != nsIBrowserDOMWindow::OPEN_CURRENTWINDOW);
+
+  {
+    dom::AutoNoJSAPI nojsapi;
+
+    uint32_t flags = nsIBrowserDOMWindow::OPEN_NEW;
+    if (aForceNoOpener) {
+      flags |= nsIBrowserDOMWindow::OPEN_NO_OPENER;
+    }
+
+    // Get a new rendering area from the browserDOMWin.  We don't want
+    // to be starting any loads here, so get it with a null URI.
+    //
+    // This method handles setting the opener for us, so we don't need to set it
+    // ourselves.
+    return browserDOMWin->OpenURI(nullptr, aParent,
+                                  openLocation,
+                                  flags, aReturn);
+  }
+}
+
+//*****************************************************************************
+// nsContentTreeOwner: Accessors
+//*****************************************************************************
+
+#if defined(XP_MACOSX)
+class nsContentTitleSettingEvent : public Runnable
+{
+public:
+  nsContentTitleSettingEvent(dom::Element* dse, const nsAString& wtm)
+    : mElement(dse),
+      mTitleDefault(wtm) {}
+
+  NS_IMETHOD Run() override
+  {
+    ErrorResult rv;
+    mElement->SetAttribute(NS_LITERAL_STRING("titledefault"), mTitleDefault, rv);
+    mElement->RemoveAttribute(NS_LITERAL_STRING("titlemodifier"), rv);
+    return NS_OK;
+  }
+
+private:
+  nsCOMPtr<dom::Element> mElement;
+  nsString mTitleDefault;
+};
+#endif
+
+void nsContentTreeOwner::XULWindow(nsXULWindow* aXULWindow)
+{
+   mXULWindow = aXULWindow;
+   if (mXULWindow && mPrimary) {
+      // Get the window title modifiers
+      nsCOMPtr<dom::Element> docShellElement = mXULWindow->GetWindowDOMElement();
+
+      nsAutoString   contentTitleSetting;
+
+      if(docShellElement)
+         {
+         docShellElement->GetAttribute(NS_LITERAL_STRING("contenttitlesetting"), contentTitleSetting);
+         if(contentTitleSetting.EqualsLiteral("true"))
+            {
+            mContentTitleSetting = true;
+            docShellElement->GetAttribute(NS_LITERAL_STRING("titledefault"), mTitleDefault);
+            docShellElement->GetAttribute(NS_LITERAL_STRING("titlemodifier"), mWindowTitleModifier);
+            docShellElement->GetAttribute(NS_LITERAL_STRING("titlepreface"), mTitlePreface);
+
+#if defined(XP_MACOSX)
+            // On OS X, treat the titlemodifier like it's the titledefault, and don't ever append
+            // the separator + appname.
+            if (mTitleDefault.IsEmpty()) {
+                NS_DispatchToCurrentThread(
+                    new nsContentTitleSettingEvent(docShellElement,
+                                                   mWindowTitleModifier));
+                mTitleDefault = mWindowTitleModifier;
+                mWindowTitleModifier.Truncate();
+            }
+#endif
+            docShellElement->GetAttribute(NS_LITERAL_STRING("titlemenuseparator"), mTitleSeparator);
+            }
+         }
+      else
+         {
+         NS_ERROR("This condition should never happen.  If it does, "
+            "we just won't get a modifier, but it still shouldn't happen.");
+         }
+      }
+}
+
+nsXULWindow* nsContentTreeOwner::XULWindow()
+{
+   return mXULWindow;
+}
+
+//*****************************************************************************
+//*** nsSiteWindow implementation
+//*****************************************************************************
+
+nsSiteWindow::nsSiteWindow(nsContentTreeOwner *aAggregator)
+{
+  mAggregator = aAggregator;
+}
+
+nsSiteWindow::~nsSiteWindow()
+{
+}
+
+NS_IMPL_ADDREF_USING_AGGREGATOR(nsSiteWindow, mAggregator)
+NS_IMPL_RELEASE_USING_AGGREGATOR(nsSiteWindow, mAggregator)
+
+NS_INTERFACE_MAP_BEGIN(nsSiteWindow)
+  NS_INTERFACE_MAP_ENTRY(nsISupports)
+  NS_INTERFACE_MAP_ENTRY(nsIEmbeddingSiteWindow)
+NS_INTERFACE_MAP_END_AGGREGATED(mAggregator)
+
+NS_IMETHODIMP
+nsSiteWindow::SetDimensions(uint32_t aFlags,
+                    int32_t aX, int32_t aY, int32_t aCX, int32_t aCY)
+{
+  // XXX we're ignoring aFlags
+  return mAggregator->SetPositionAndSize(aX, aY, aCX, aCY,
+                                         nsIBaseWindow::eRepaint);
+}
+
+NS_IMETHODIMP
+nsSiteWindow::GetDimensions(uint32_t aFlags,
+                    int32_t *aX, int32_t *aY, int32_t *aCX, int32_t *aCY)
+{
+  // XXX we're ignoring aFlags
+  return mAggregator->GetPositionAndSize(aX, aY, aCX, aCY);
+}
+
+NS_IMETHODIMP
+nsSiteWindow::SetFocus(void)
+{
+#if 0
+  /* This implementation focuses the main document and could make sense.
+     However this method is actually being used from within
+     nsGlobalWindow::Focus (providing a hook for MDI embedding apps)
+     and it's better for our purposes to not pick a document and
+     focus it, but allow nsGlobalWindow to carry on unhindered.
+  */
+  nsXULWindow *window = mAggregator->XULWindow();
+  if (window) {
+    nsCOMPtr<nsIDocShell> docshell;
+    window->GetDocShell(getter_AddRefs(docshell));
+    if (docShell) {
+      nsCOMPtr<nsPIDOMWindowOuter> domWindow(docShell->GetWindow());
+      if (domWindow)
+        domWindow->Focus();
+    }
+  }
+#endif
+  return NS_OK;
+}
+
+/* this implementation focuses another window. if there isn't another
+   window to focus, we do nothing. */
+NS_IMETHODIMP
+nsSiteWindow::Blur(void)
+{
+  NS_DEFINE_CID(kWindowMediatorCID, NS_WINDOWMEDIATOR_CID);
+
+  nsCOMPtr<nsISimpleEnumerator> windowEnumerator;
+  nsCOMPtr<nsIXULWindow>        xulWindow;
+  bool                          more, foundUs;
+  nsXULWindow                  *ourWindow = mAggregator->XULWindow();
+
+  {
+    nsCOMPtr<nsIWindowMediator> windowMediator(do_GetService(kWindowMediatorCID));
+    if (windowMediator)
+      windowMediator->GetZOrderXULWindowEnumerator(0, true,
+                        getter_AddRefs(windowEnumerator));
+  }
+
+  if (!windowEnumerator)
+    return NS_ERROR_FAILURE;
+
+  // step through the top-level windows
+  foundUs = false;
+  windowEnumerator->HasMoreElements(&more);
+  while (more) {
+
+    nsCOMPtr<nsISupports>  nextWindow;
+    nsCOMPtr<nsIXULWindow> nextXULWindow;
+
+    windowEnumerator->GetNext(getter_AddRefs(nextWindow));
+    nextXULWindow = do_QueryInterface(nextWindow);
+
+    // got it!(?)
+    if (foundUs) {
+      xulWindow = nextXULWindow;
+      break;
+    }
+
+    // remember the very first one, in case we have to wrap
+    if (!xulWindow)
+      xulWindow = nextXULWindow;
+
+    // look for us
+    if (nextXULWindow == ourWindow)
+      foundUs = true;
+
+    windowEnumerator->HasMoreElements(&more);
+  }
+
+  // change focus to the window we just found
+  if (xulWindow) {
+    nsCOMPtr<nsIDocShell> docshell;
+    xulWindow->GetDocShell(getter_AddRefs(docshell));
+    if (!docshell) {
+      return NS_OK;
+    }
+
+    nsCOMPtr<nsPIDOMWindowOuter> domWindow = docshell->GetWindow();
+    if (domWindow)
+      domWindow->Focus();
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsSiteWindow::GetVisibility(bool *aVisibility)
+{
+  return mAggregator->GetVisibility(aVisibility);
+}
+
+NS_IMETHODIMP
+nsSiteWindow::SetVisibility(bool aVisibility)
+{
+  return mAggregator->SetVisibility(aVisibility);
+}
+
+NS_IMETHODIMP
+nsSiteWindow::GetTitle(char16_t * *aTitle)
+{
+  return mAggregator->GetTitle(aTitle);
+}
+
+NS_IMETHODIMP
+nsSiteWindow::SetTitle(const char16_t * aTitle)
+{
+  return mAggregator->SetTitle(aTitle);
+}
+
+NS_IMETHODIMP
+nsSiteWindow::GetSiteWindow(void **aSiteWindow)
+{
+  return mAggregator->GetParentNativeWindow(aSiteWindow);
+}
+
diff --git a/xpfe/appshell/nsContentTreeOwner.h b/xpfe/appshell/nsContentTreeOwner.h
new file mode 100644
index 000000000..d6a0d42b3
--- /dev/null
+++ b/xpfe/appshell/nsContentTreeOwner.h
@@ -0,0 +1,63 @@
+/* -*- Mode: IDL; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsContentTreeOwner_h__
+#define nsContentTreeOwner_h__
+
+// Helper Classes
+#include "nsCOMPtr.h"
+#include "nsString.h"
+
+// Interfaces Needed
+#include "nsIBaseWindow.h"
+#include "nsIDocShellTreeOwner.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsIWebBrowserChrome3.h"
+#include "nsIWindowProvider.h"
+
+class nsXULWindow;
+class nsSiteWindow;
+
+class nsContentTreeOwner final : public nsIDocShellTreeOwner,
+                                 public nsIBaseWindow,
+                                 public nsIInterfaceRequestor,
+                                 public nsIWebBrowserChrome3,
+                                 public nsIWindowProvider
+{
+friend class nsXULWindow;
+friend class nsSiteWindow;
+
+public:
+   NS_DECL_ISUPPORTS
+
+   NS_DECL_NSIBASEWINDOW
+   NS_DECL_NSIDOCSHELLTREEOWNER
+   NS_DECL_NSIINTERFACEREQUESTOR
+   NS_DECL_NSIWEBBROWSERCHROME
+   NS_DECL_NSIWEBBROWSERCHROME2
+   NS_DECL_NSIWEBBROWSERCHROME3
+   NS_DECL_NSIWINDOWPROVIDER
+
+protected:
+   explicit nsContentTreeOwner(bool fPrimary);
+   virtual ~nsContentTreeOwner();
+
+   void XULWindow(nsXULWindow* aXULWindow);
+   nsXULWindow* XULWindow();
+
+protected:
+   nsXULWindow      *mXULWindow;
+   nsSiteWindow    *mSiteWindow;
+   bool              mPrimary;
+   bool              mContentTitleSetting;
+   nsString          mWindowTitleModifier;
+   nsString          mTitleSeparator;
+   nsString          mTitlePreface;
+   nsString          mTitleDefault;
+};
+
+#endif /* nsContentTreeOwner_h__ */
diff --git a/xpfe/appshell/nsIAppShellService.idl b/xpfe/appshell/nsIAppShellService.idl
new file mode 100644
index 000000000..e7d96a5d1
--- /dev/null
+++ b/xpfe/appshell/nsIAppShellService.idl
@@ -0,0 +1,150 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIXULWindow;
+interface nsIWindowlessBrowser;
+interface nsIURI;
+interface mozIDOMWindowProxy;
+interface nsIAppShell;
+interface nsITabParent;
+
+[ptr] native JSContext(JSContext);
+
+%{C++
+#include "js/TypeDecls.h"
+%}
+
+[scriptable, uuid(19266025-354c-4bb9-986b-3483b2b1cdef)]
+interface nsIAppShellService : nsISupports
+{
+  /**
+   * Create a window, which will be initially invisible.
+   * @param aParent the parent window.  Can be null.
+   * @param aUrl the contents of the new window.
+   * @param aChromeMask chrome flags affecting the kind of OS border
+   *                    given to the window. see nsIBrowserWindow for
+   *                    bit/flag definitions.
+   * @param aCallbacks interface providing C++ hooks for window initialization
+   *                   before the window is made visible.  Can be null.
+   *                   Deprecated.
+   * @param aInitialWidth width, in pixels, of the window.  Width of window
+   *                      at creation.  Can be overridden by the "width"
+   *                      tag in the XUL.  Set to NS_SIZETOCONTENT to force
+   *                      the window to wrap to its contents.
+   * @param aInitialHeight like aInitialWidth, but subtly different.
+   * @param aOpeningTab The TabParent that requested that this window be opened.
+   *                    Can be left null.
+   * @param aOpenerWindow The Window Proxy which requested that this window be opened.
+   *                      Can be left null.
+   */
+  const long SIZE_TO_CONTENT = -1;
+  nsIXULWindow createTopLevelWindow(in nsIXULWindow aParent,
+                                    in nsIURI aUrl, 
+                                    in uint32_t aChromeMask,
+                                    in long aInitialWidth,
+                                    in long aInitialHeight,
+                                    in nsITabParent aOpeningTab,
+                                    in mozIDOMWindowProxy aOpenerWindow);
+
+  /**
+   * This is the constructor for creating an invisible DocShell.
+   * It is used to simulate DOM windows without an actual physical
+   * representation.
+   * @param aIsChrome Set true if you want to use it for chrome content.
+   */
+  nsIWindowlessBrowser createWindowlessBrowser([optional] in bool aIsChrome);
+
+  [noscript]
+  void createHiddenWindow();
+
+  void destroyHiddenWindow();
+
+  /**
+   * B2G multi-screen support. When open another top-level window on b2g,
+   * a screen ID is needed for identifying which screen this window is
+   * opened to.
+   * @param aScreenId Differentiate screens of windows. It is platform-
+   *                  specific due to the hardware limitation for now.
+   */
+  [noscript]
+  void setScreenId(in uint32_t aScreenId);
+
+  /**
+   * Return the (singleton) application hidden window, automatically created
+   * and maintained by this AppShellService.
+   * @param aResult the hidden window.  Do not unhide hidden window.
+   *                Do not taunt hidden window.
+   */
+  readonly attribute nsIXULWindow hiddenWindow;
+
+  /**
+   * Return the (singleton) application hidden window, automatically created
+   * and maintained by this AppShellService.
+   * @param aResult the hidden window.  Do not unhide hidden window.
+   *                Do not taunt hidden window.
+   */
+  readonly attribute mozIDOMWindowProxy hiddenDOMWindow;
+
+  /**
+   * Return the (singleton) application hidden private window, automatically
+   * created and maintained by this AppShellService.  This window is created
+   * in private browsing mode.
+   * @param aResult the hidden private window.  Do not unhide hidden window.
+   *                Do not taunt hidden window.
+   */
+  readonly attribute nsIXULWindow hiddenPrivateWindow;
+
+  /**
+   * Return the (singleton) application hidden private window, automatically
+   * created and maintained by this AppShellService.  This window is created
+   * in private browsing mode.
+   * @param aResult the hidden private window.  Do not unhide hidden window.
+   *                Do not taunt hidden window.
+   */
+  readonly attribute mozIDOMWindowProxy hiddenPrivateDOMWindow;
+
+  /**
+   * Return true if the application hidden window was provided by the
+   * application. If it wasn't, the default hidden window was used. This will
+   * usually be false on all non-mac platforms.
+   */
+  readonly attribute boolean applicationProvidedHiddenWindow;
+
+  /**
+   * Add a window to the application's registry of windows.  These windows
+   * are generally shown in the Windows taskbar, and the application
+   * knows it can't quit until it's out of registered windows.
+   * @param aWindow the window to register
+   * @note When this method is successful, it fires the global notification
+   *       "xul-window-registered"
+   */
+  void registerTopLevelWindow(in nsIXULWindow aWindow);
+
+  /**
+   * Remove a window from the application's window registry. Note that
+   * this method won't automatically attempt to quit the app when
+   * the last window is unregistered. For that, see Quit().
+   * @param aWindow you see the pattern
+   */
+  void unregisterTopLevelWindow(in nsIXULWindow aWindow);
+
+  /**
+   * Whether the hidden private window has been lazily created.
+   */
+  [noscript]
+  readonly attribute boolean hasHiddenPrivateWindow;
+
+  /**
+   * Start/stop tracking lags in the event loop.
+   * If the event loop gets unresponsive, a "event-loop-lag" notification
+   * is sent. Note that calling `startEventLoopLagTracking` when tracking
+   * is already enabled has no effect.
+   * @return true if tracking succeeded.
+   */
+  bool startEventLoopLagTracking();
+  void stopEventLoopLagTracking();
+};
diff --git a/xpfe/appshell/nsIPopupWindowManager.idl b/xpfe/appshell/nsIPopupWindowManager.idl
new file mode 100644
index 000000000..4e6cb99b3
--- /dev/null
+++ b/xpfe/appshell/nsIPopupWindowManager.idl
@@ -0,0 +1,35 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/**
+ * This is the interface to the Popup Window Manager: an object which
+ * maintains popup window permissions by website.
+ */
+
+#include "nsISupports.idl"
+
+interface nsIPrincipal;
+
+[scriptable, uuid(66386aa9-2088-4bae-82c7-9f58bc02be64)]
+interface nsIPopupWindowManager : nsISupports {
+
+  /**
+   * These values are returned by the testPermission method
+   */
+  const uint32_t ALLOW_POPUP = 1;
+  const uint32_t DENY_POPUP = 2;
+  const uint32_t ALLOW_POPUP_WITH_PREJUDICE = 3;
+
+  /**
+   * Test whether a website has permission to show a popup window.
+   * @param   principal is the principal to be tested
+   * @return  one of the enumerated permission actions defined above
+   */
+  uint32_t testPermission(in nsIPrincipal principal);
+};
+
+%{ C++
+#define NS_POPUPWINDOWMANAGER_CONTRACTID "@mozilla.org/PopupWindowManager;1"
+%}
diff --git a/xpfe/appshell/nsIWindowMediator.idl b/xpfe/appshell/nsIWindowMediator.idl
new file mode 100644
index 000000000..b38297594
--- /dev/null
+++ b/xpfe/appshell/nsIWindowMediator.idl
@@ -0,0 +1,206 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+#include "nsISimpleEnumerator.idl"
+
+%{C++
+#define NS_WINDOWMEDIATOR_CID \
+{ 0x79a2b7cc, 0xf05b, 0x4605, \
+  { 0xbf, 0xa0, 0xfa, 0xc5, 0x4f, 0x27, 0xee, 0xc8 } }
+
+#define NS_WINDOWMEDIATOR_CONTRACTID \
+  "@mozilla.org/appshell/window-mediator;1"
+%}
+
+interface mozIDOMWindow;
+interface mozIDOMWindowProxy;
+interface nsIXULWindow;
+interface nsIWidget;
+interface nsIWindowMediatorListener;
+
+[scriptable, uuid(df0da056-357d-427f-bafd-e6cbf19c9381)]
+interface nsIWindowMediator: nsISupports
+{
+  /** Return an enumerator which iterates over all windows of type aWindowType
+    * from the oldest window to the youngest.
+    * @param  aWindowType the returned enumerator will enumerate only
+    *                     windows of this type. ("type" is the
+    *                     |windowtype| attribute of the XML <window> element.)
+    *                     If null, all windows will be enumerated.
+    * @return an enumerator of nsIDOMWindows.  Note that windows close
+    *         asynchronously in many cases, so windows returned from this
+    *         enumerator can have .closed set to true.  Caveat enumerator!
+    */
+  nsISimpleEnumerator getEnumerator(in wstring aWindowType);
+
+  /** Identical to getEnumerator except:
+    * @return an enumerator of nsIXULWindows
+  */
+  nsISimpleEnumerator getXULWindowEnumerator(in wstring aWindowType);
+
+  /** Return an enumerator which iterates over all windows of type aWindowType
+    * in their z (front-to-back) order. Note this interface makes
+    * no requirement that a window couldn't be revisited if windows
+    * are re-ordered while z-order enumerators are active.
+    * @param  aWindowType the returned enumerator will enumerate only
+    *                     windows of this type. ("type" is the
+    *                     |windowtype| attribute of the XML <window> element.)
+    *                     If null, all windows will be enumerated.
+    * @param  aFrontToBack if true, the enumerator enumerates windows in order
+    *                      from front to back. back to front if false.
+    * @return an enumerator of nsIDOMWindows
+    */
+  nsISimpleEnumerator getZOrderDOMWindowEnumerator(in wstring aWindowType,
+                        in boolean aFrontToBack);
+
+  /** Identical to getZOrderDOMWindowEnumerator except:
+    * @return an enumerator of nsIXULWindows
+    */
+  nsISimpleEnumerator getZOrderXULWindowEnumerator(in wstring aWindowType,
+                        in boolean aFrontToBack);
+
+  /** This is a shortcut for simply fetching the first window in
+    * front to back order.
+    * @param  aWindowType return the topmost window of this type.
+    *                     ("type" is the |windowtype| attribute of
+    *                     the XML <window> element.)
+    *                     If null, return the topmost window of any type.
+    * @return the topmost window
+    */
+  mozIDOMWindowProxy getMostRecentWindow(in wstring aWindowType);
+
+  /**
+   * Return the outer window with the given ID, if any.  Can return null.
+   */
+  mozIDOMWindowProxy getOuterWindowWithId(in unsigned long long aOuterWindowID);
+
+  /**
+    * Return the inner window with the given current window ID, if any.
+    * Can return null if no inner window with the ID exists or if it's not
+    * a current inner anymore.
+    */
+  mozIDOMWindow getCurrentInnerWindowWithId(in unsigned long long aInnerWindowID);
+
+  /** Add the window to the list of known windows. Listeners (see
+    * addListener) will be notified through their onOpenWindow method.
+    * @param aWindow the window to add
+    */
+  [noscript] void registerWindow(in nsIXULWindow aWindow);
+
+  /** Remove the window from the list of known windows. Listeners (see
+    * addListener) will be be notified through their onCloseWindow method.
+    * @param aWindow the window to remove
+    */
+  [noscript] void unregisterWindow(in nsIXULWindow aWindow);
+
+  /** Call this method when a window gains focus. It's a primitive means of
+    * determining the most recent window. It's no longer necessary and it
+    * really should be removed.
+    * @param aWindow the window which has gained focus
+    */
+  [noscript] void updateWindowTimeStamp(in nsIXULWindow aWindow);
+
+  /** Call this method when a window's title changes. Listeners (see
+    * addListener) will be notified through their onWindowTitleChange method.
+    * @param aWindow the window whose title has changed
+    * @param inTitle the window's new title
+    */
+  [noscript] void updateWindowTitle(in nsIXULWindow aWindow,
+                                    in wstring inTitle );
+
+  /* z-ordering: */
+
+  const unsigned long zLevelTop    = 1;
+  const unsigned long zLevelBottom = 2;
+  const unsigned long zLevelBelow  = 3; // below some window
+
+  /** A window wants to be moved in z-order. Calculate whether and how
+    * it should be constrained. Note this method is advisory only:
+    * it changes nothing either in WindowMediator's internal state
+    * or with the window.
+    * Note it compares the nsIXULWindow to nsIWidgets. A pure interface
+    * would use all nsIXULWindows. But we expect this to be called from
+    * callbacks originating in native window code. They are expected to
+    * hand us comparison values which are pulled from general storage
+    * in the native widget, and may not correspond to an nsIWidget at all.
+    * For that reason this interface requires only objects one step
+    * removed from the native window (nsIWidgets), and its implementation
+    * must be very understanding of what may be completely invalid
+    * pointers in those parameters.
+    *
+    * @param inWindow the window in question
+    * @param inPosition requested position
+    *                   values: zLevelTop: topmost window. zLevelBottom: bottom.
+    *                   zLevelBelow: below ioBelow. (the value of ioBelow will
+    *                   be ignored for zLevelTop and Bottom.)
+    * @param inBelow if inPosition==zLevelBelow, the window
+    *                 below which inWindow wants to be placed. Otherwise this
+    *                 variable is ignored.
+    * @param outPosition constrained position, values like inPosition.
+    * @param outBelow if outPosition==zLevelBelow, the window
+    *                 below which inWindow should be placed. Otherwise this
+    *                 this value will be null.
+    * @return PR_TRUE if the position returned is different from
+    *         the position given.
+    */
+
+  [noscript] boolean calculateZPosition(in nsIXULWindow   inWindow,
+                                        in unsigned long  inPosition,
+                                        in nsIWidget      inBelow,
+                                        out unsigned long outPosition,
+                                        out nsIWidget     outBelow);
+
+  /** A window has been positioned behind another. Inform WindowMediator
+    * @param inWindow the window in question
+    * @param inPosition new position. values:
+    *                   zLevelTop: topmost window.
+    *                   zLevelBottom: bottom.
+    *                   zLevelBelow: below inBelow. (inBelow is ignored
+    *                                for other values of inPosition.)
+    * @param inBelow the window inWindow is behind, if zLevelBelow
+    */
+  [noscript] void setZPosition(in nsIXULWindow inWindow,
+                               in unsigned long inPosition,
+                               in nsIXULWindow inBelow);
+
+  /** Return the window's Z level (as defined in nsIXULWindow).
+    * @param aWindow the window in question
+    * @return aWindow's z level
+    */
+  [noscript] uint32_t getZLevel(in nsIXULWindow aWindow);
+
+  /** Set the window's Z level (as defined in nsIXULWindow). The implementation
+    * will reposition the window as necessary to match its new Z level.
+    * The implementation will assume a window's Z level to be
+    * nsIXULWindow::normalZ until it has been informed of a different level.
+    * @param aWindow the window in question
+    * @param aZLevel the window's new Z level
+    */
+  [noscript] void setZLevel(in nsIXULWindow aWindow, in uint32_t aZLevel);
+
+  /** Register a listener for window status changes.
+    * keeps strong ref? (to be decided)
+    * @param aListener the listener to register
+    */
+  void addListener(in nsIWindowMediatorListener aListener);
+
+  /** Unregister a listener of window status changes.
+    * @param aListener the listener to unregister
+    */
+  void removeListener(in nsIWindowMediatorListener aListener);
+};
+
+// XXXcatalinb: This should be merged to nsIWindowMediator. Using this
+// to avoid UUID change in aurora.
+[scriptable, uuid(b9ed4063-39a2-4302-8e5c-7287eef021fe)]
+interface nsIWindowMediator_44 : nsIWindowMediator
+{
+  /**
+   * Same as getMostRecentWindow, but ignores private browsing
+   * windows.
+   */
+  mozIDOMWindowProxy getMostRecentNonPBWindow(in wstring aWindowType);
+};
diff --git a/xpfe/appshell/nsIWindowMediatorListener.idl b/xpfe/appshell/nsIWindowMediatorListener.idl
new file mode 100644
index 000000000..459e3b6ab
--- /dev/null
+++ b/xpfe/appshell/nsIWindowMediatorListener.idl
@@ -0,0 +1,19 @@
+/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+interface nsIXULWindow;
+
+[scriptable, uuid(2F276982-0D60-4377-A595-D350BA516395)]
+interface nsIWindowMediatorListener : nsISupports
+{
+    void onWindowTitleChange(in nsIXULWindow window,
+                             in wstring newTitle);
+
+    void onOpenWindow(in nsIXULWindow window);
+    void onCloseWindow(in nsIXULWindow window);
+};
+
diff --git a/xpfe/appshell/nsIWindowlessBrowser.idl b/xpfe/appshell/nsIWindowlessBrowser.idl
new file mode 100644
index 000000000..c959e47a4
--- /dev/null
+++ b/xpfe/appshell/nsIWindowlessBrowser.idl
@@ -0,0 +1,27 @@
+/* -*- Mode: IDL; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsIWebNavigation.idl"
+
+/**
+ * This interface represents a nsIWebBrowser instance with no associated OS
+ * window. Its main function is to manage the lifetimes of those windows.
+ * A strong reference to this object must be held until the window is
+ * ready to be destroyed.
+ */
+[scriptable, uuid(abb46f48-abfc-41bf-aa9a-7feccefcf977)]
+interface nsIWindowlessBrowser : nsIWebNavigation
+{
+  /**
+   * "Closes" the windowless browser and destroys its associated nsIWebBrowser
+   * and docshell.
+   *
+   * This method *must* be called for every windowless browser before its last
+   * reference is released.
+   */
+  void close();
+};
+
diff --git a/xpfe/appshell/nsIXULBrowserWindow.idl b/xpfe/appshell/nsIXULBrowserWindow.idl
new file mode 100644
index 000000000..40f1898c8
--- /dev/null
+++ b/xpfe/appshell/nsIXULBrowserWindow.idl
@@ -0,0 +1,78 @@
+/* -*- Mode: IDL; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+#include "nsIURI.idl"
+#include "nsIDOMNode.idl"
+
+interface nsIRequest;
+interface nsIDOMElement;
+interface nsIInputStream;
+interface nsIDocShell;
+interface nsITabParent;
+interface mozIDOMWindowProxy;
+
+/**
+ * The nsIXULBrowserWindow supplies the methods that may be called from the
+ * internals of the browser area to tell the containing xul window to update
+ * its ui. 
+ */
+[scriptable, uuid(a8675fa9-c8b4-4350-9803-c38f344a9e38)]
+interface nsIXULBrowserWindow : nsISupports
+{
+  /**
+   * Sets the status according to JS' version of status.
+   */
+  void setJSStatus(in AString status);
+
+  /**
+   * Tells the object implementing this function what link we are currently
+   * over.
+   */
+  void setOverLink(in AString link, in nsIDOMElement element);
+
+  /**
+   * Determines the appropriate target for a link.
+   */
+  AString onBeforeLinkTraversal(in AString originalTarget,
+                                in nsIURI linkURI,
+                                in nsIDOMNode linkNode,
+                                in boolean isAppTab);
+
+  /**
+   * Find the initial browser of the window and set its remote attribute.
+   * This can be used to ensure that there is a remote browser in a new
+   * window when it first spawns.
+   *
+   */
+  nsITabParent forceInitialBrowserRemote();
+  void forceInitialBrowserNonRemote(in mozIDOMWindowProxy openerWindow);
+
+  /**
+   * Determines whether a load should continue.
+   *
+   * @param aDocShell
+   *        The docshell performing the load.
+   * @param aURI
+   *        The URI being loaded.
+   * @param aReferrer
+   *        The referrer of the load.
+   */
+  bool shouldLoadURI(in nsIDocShell    aDocShell,
+                     in nsIURI         aURI,
+                     in nsIURI         aReferrer);
+  /**
+   * Show/hide a tooltip (when the user mouses over a link, say).
+   */
+  void showTooltip(in long x, in long y, in AString tooltip, in AString direction);
+  void hideTooltip();
+
+  /**
+   * Return the number of tabs in this window.
+   */
+  uint32_t getTabCount();
+};
+
diff --git a/xpfe/appshell/nsIXULWindow.idl b/xpfe/appshell/nsIXULWindow.idl
new file mode 100644
index 000000000..8db12adb6
--- /dev/null
+++ b/xpfe/appshell/nsIXULWindow.idl
@@ -0,0 +1,168 @@
+/* -*- Mode: IDL; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsISupports.idl"
+
+/**
+ * The nsIXULWindow
+ *
+ * When the window is destroyed, it will fire a "xul-window-destroyed"
+ * notification through the global observer service.
+ */
+
+interface nsIDocShell;
+interface nsIDocShellTreeItem;
+interface nsIXULBrowserWindow;
+interface nsITabParent;
+interface mozIDOMWindowProxy;
+
+[scriptable, uuid(d6d7a014-e28d-4c9d-8727-1cf6d870619b)]
+interface nsIXULWindow : nsISupports
+{
+  /**
+   * The docshell owning the XUL for this window.
+   */
+  readonly attribute nsIDocShell docShell;
+
+  /**
+   * Indicates if this window is instrinsically sized.	
+   */
+  attribute boolean intrinsicallySized;
+
+  /**
+   * The primary content shell.  
+   *
+   * Note that this is a docshell tree item and therefore can not be assured of
+   * what object it is. It could be an editor, a docshell, or a browser object.
+   * Or down the road any other object that supports being a DocShellTreeItem
+   * Query accordingly to determine the capabilities.
+   */
+  readonly attribute nsIDocShellTreeItem primaryContentShell;
+
+  /**
+   * In multiprocess case we may not have primaryContentShell but
+   * primaryTabParent.
+   */
+  readonly attribute nsITabParent primaryTabParent;
+
+  void tabParentAdded(in nsITabParent aTab, in boolean aPrimary);
+  void tabParentRemoved(in nsITabParent aTab);
+
+  /**
+   * The content shell specified by the supplied id.
+   *
+   * Note that this is a docshell tree item and therefore can not be assured of
+   * what object it is.  It could be an editor, a docshell, or a browser object.
+   * Or down the road any other object that supports being a DocShellTreeItem
+   * Query accordingly to determine the capabilities.
+   */
+  nsIDocShellTreeItem getContentShellById(in wstring ID);
+
+  /**
+   * Tell this window that it has picked up a child XUL window
+   * @param aChild the child window being added
+   */
+  void addChildWindow(in nsIXULWindow aChild);
+
+  /**
+   * Tell this window that it has lost a child XUL window
+   * @param aChild the child window being removed
+   */
+  void removeChildWindow(in nsIXULWindow aChild);
+
+  /**
+   * Move the window to a centered position.
+   * @param aRelative If not null, the window relative to which the window is
+   *                  moved. See aScreen parameter for details.
+   * @param aScreen   PR_TRUE to center the window relative to the screen
+   *                  containing aRelative if aRelative is not null. If
+   *                  aRelative is null then relative to the screen of the
+   *                  opener window if it was initialized by passing it to
+   *                  nsWebShellWindow::Initialize. Failing that relative to
+   *                  the main screen.
+   *                  PR_FALSE to center it relative to aRelative itself.
+   * @param aAlert    PR_TRUE to move the window to an alert position,
+   *                  generally centered horizontally and 1/3 down from the top.
+   */
+  void center(in nsIXULWindow aRelative, in boolean aScreen, in boolean aAlert);
+
+  /**
+   * Shows the window as a modal window. That is, ensures that it is visible
+   * and runs a local event loop, exiting only once the window has been closed.
+   */
+  void showModal();
+
+  const unsigned long lowestZ = 0;
+  const unsigned long loweredZ = 4;  /* "alwaysLowered" attribute */
+  const unsigned long normalZ = 5;
+  const unsigned long raisedZ = 6;   /* "alwaysRaised" attribute */
+  const unsigned long highestZ = 9;
+
+  attribute unsigned long zLevel;
+
+  /**
+   * contextFlags are from nsIWindowCreator2
+   */
+  attribute uint32_t contextFlags;
+
+  attribute uint32_t chromeFlags;
+
+  /**
+   * Begin assuming |chromeFlags| don't change hereafter, and assert
+   * if they do change.  The state change is one-way and idempotent.
+   */
+  void assumeChromeFlagsAreFrozen();
+
+  /**
+   * Create a new window.
+   * @param aChromeFlags see nsIWebBrowserChrome
+   * @param aOpeningTab the TabParent that requested this new window be opened.
+   *                    Can be left null.
+   * @param aOpener The window which is requesting that this new window be opened.
+   * @return the newly minted window
+   */
+  nsIXULWindow createNewWindow(in int32_t aChromeFlags,
+                               in nsITabParent aOpeningTab,
+                               in mozIDOMWindowProxy aOpener);
+
+  attribute nsIXULBrowserWindow XULBrowserWindow;
+
+  /**
+   * Back-door method to force application of chrome flags at a particular
+   * time.  Do NOT call this unless you know what you're doing!  In particular,
+   * calling this when this XUL window doesn't yet have a document in its
+   * docshell could cause problems.
+   */
+  [noscript] void applyChromeFlags();
+
+  /**
+   * Given the dimensions of some content area held within this
+   * XUL window, and assuming that that content area will change
+   * its dimensions in linear proportion to the dimensions of this
+   * XUL window, changes the size of the XUL window so that the
+   * content area reaches a particular size.
+   *
+   * We need to supply the content area dimensions because sometimes
+   * the child's nsDocShellTreeOwner needs to propagate a SizeShellTo
+   * call to the parent. But the shellItem argument of the call will
+   * not be available on the parent side.
+   *
+   * Note: this is an internal method, other consumers should never call this.
+   *
+   * @param aDesiredWidth
+   *        The desired width of the content area in device pixels.
+   * @param aDesiredHeight
+   *        The desired height of the content area in device pixels.
+   * @param shellItemWidth
+   *        The current width of the content area.
+   * @param shellItemHeight
+   *        The current height of the content area.
+   */
+  [noscript, notxpcom] void sizeShellToWithLimit(in int32_t aDesiredWidth,
+                                                 in int32_t aDesiredHeight,
+                                                 in int32_t shellItemWidth,
+                                                 in int32_t shellItemHeight);
+};
diff --git a/xpfe/appshell/nsWebShellWindow.cpp b/xpfe/appshell/nsWebShellWindow.cpp
new file mode 100644
index 000000000..288d94759
--- /dev/null
+++ b/xpfe/appshell/nsWebShellWindow.cpp
@@ -0,0 +1,911 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+
+#include "nsWebShellWindow.h"
+
+#include "nsLayoutCID.h"
+#include "nsContentCID.h"
+#include "nsIWeakReference.h"
+#include "nsIContentViewer.h"
+#include "nsIComponentManager.h"
+#include "nsIServiceManager.h"
+#include "nsIURL.h"
+#include "nsIIOService.h"
+#include "nsIURL.h"
+#include "nsNetCID.h"
+#include "nsIStringBundle.h"
+#include "nsReadableUtils.h"
+
+#include "nsContentUtils.h"
+#include "nsEscape.h"
+#include "nsPIDOMWindow.h"
+#include "nsIWebNavigation.h"
+#include "nsIWindowWatcher.h"
+
+#include "nsIDOMXULElement.h"
+
+#include "nsWidgetInitData.h"
+#include "nsWidgetsCID.h"
+#include "nsIWidget.h"
+#include "nsIWidgetListener.h"
+
+#include "nsIDOMCharacterData.h"
+#include "nsIDOMNodeList.h"
+
+#include "nsITimer.h"
+#include "nsXULPopupManager.h"
+
+
+#include "nsIDOMXULDocument.h"
+
+#include "nsFocusManager.h"
+
+#include "nsIWebProgress.h"
+#include "nsIWebProgressListener.h"
+
+#include "nsIDocument.h"
+#include "nsIDOMDocument.h"
+#include "nsIDOMNode.h"
+#include "nsIDOMElement.h"
+#include "nsIDocumentLoaderFactory.h"
+#include "nsIObserverService.h"
+#include "prprf.h"
+
+#include "nsIScreenManager.h"
+#include "nsIScreen.h"
+
+#include "nsIContent.h" // for menus
+#include "nsIScriptSecurityManager.h"
+
+// For calculating size
+#include "nsIPresShell.h"
+#include "nsPresContext.h"
+
+#include "nsIBaseWindow.h"
+#include "nsIDocShellTreeItem.h"
+
+#include "mozilla/Attributes.h"
+#include "mozilla/DebugOnly.h"
+#include "mozilla/MouseEvents.h"
+
+#include "nsPIWindowRoot.h"
+
+#ifdef XP_MACOSX
+#include "nsINativeMenuService.h"
+#define USE_NATIVE_MENUS
+#endif
+
+using namespace mozilla;
+using namespace mozilla::dom;
+
+/* Define Class IDs */
+static NS_DEFINE_CID(kWindowCID,           NS_WINDOW_CID);
+
+#define SIZE_PERSISTENCE_TIMEOUT 500 // msec
+
+nsWebShellWindow::nsWebShellWindow(uint32_t aChromeFlags)
+  : nsXULWindow(aChromeFlags)
+  , mSPTimerLock("nsWebShellWindow.mSPTimerLock")
+  , mWidgetListenerDelegate(this)
+{
+}
+
+nsWebShellWindow::~nsWebShellWindow()
+{
+  MutexAutoLock lock(mSPTimerLock);
+  if (mSPTimer)
+    mSPTimer->Cancel();
+}
+
+NS_IMPL_ADDREF_INHERITED(nsWebShellWindow, nsXULWindow)
+NS_IMPL_RELEASE_INHERITED(nsWebShellWindow, nsXULWindow)
+
+NS_INTERFACE_MAP_BEGIN(nsWebShellWindow)
+  NS_INTERFACE_MAP_ENTRY(nsIWebProgressListener)
+NS_INTERFACE_MAP_END_INHERITING(nsXULWindow)
+
+nsresult nsWebShellWindow::Initialize(nsIXULWindow* aParent,
+                                      nsIXULWindow* aOpener,
+                                      nsIURI* aUrl,
+                                      int32_t aInitialWidth,
+                                      int32_t aInitialHeight,
+                                      bool aIsHiddenWindow,
+                                      nsITabParent *aOpeningTab,
+                                      mozIDOMWindowProxy *aOpenerWindow,
+                                      nsWidgetInitData& widgetInitData)
+{
+  nsresult rv;
+  nsCOMPtr<nsIWidget> parentWidget;
+
+  mIsHiddenWindow = aIsHiddenWindow;
+
+  int32_t initialX = 0, initialY = 0;
+  nsCOMPtr<nsIBaseWindow> base(do_QueryInterface(aOpener));
+  if (base) {
+    rv = base->GetPositionAndSize(&mOpenerScreenRect.x,
+                                  &mOpenerScreenRect.y,
+                                  &mOpenerScreenRect.width,
+                                  &mOpenerScreenRect.height);
+    if (NS_FAILED(rv)) {
+      mOpenerScreenRect.SetEmpty();
+    } else {
+      double scale;
+      if (NS_SUCCEEDED(base->GetUnscaledDevicePixelsPerCSSPixel(&scale))) {
+        mOpenerScreenRect.x = NSToIntRound(mOpenerScreenRect.x / scale);
+        mOpenerScreenRect.y = NSToIntRound(mOpenerScreenRect.y / scale);
+        mOpenerScreenRect.width = NSToIntRound(mOpenerScreenRect.width / scale);
+        mOpenerScreenRect.height = NSToIntRound(mOpenerScreenRect.height / scale);
+      }
+      initialX = mOpenerScreenRect.x;
+      initialY = mOpenerScreenRect.y;
+      ConstrainToOpenerScreen(&initialX, &initialY);
+    }
+  }
+
+  // XXX: need to get the default window size from prefs...
+  // Doesn't come from prefs... will come from CSS/XUL/RDF
+  DesktopIntRect deskRect(initialX, initialY, aInitialWidth, aInitialHeight);
+
+  // Create top level window
+  mWindow = do_CreateInstance(kWindowCID, &rv);
+  if (NS_OK != rv) {
+    return rv;
+  }
+
+  /* This next bit is troublesome. We carry two different versions of a pointer
+     to our parent window. One is the parent window's widget, which is passed
+     to our own widget. The other is a weak reference we keep here to our
+     parent WebShellWindow. The former is useful to the widget, and we can't
+     trust its treatment of the parent reference because they're platform-
+     specific. The latter is useful to this class.
+       A better implementation would be one in which the parent keeps strong
+     references to its children and closes them before it allows itself
+     to be closed. This would mimic the behaviour of OSes that support
+     top-level child windows in OSes that do not. Later.
+  */
+  nsCOMPtr<nsIBaseWindow> parentAsWin(do_QueryInterface(aParent));
+  if (parentAsWin) {
+    parentAsWin->GetMainWidget(getter_AddRefs(parentWidget));
+    mParentWindow = do_GetWeakReference(aParent);
+  }
+
+  mWindow->SetWidgetListener(&mWidgetListenerDelegate);
+  rv = mWindow->Create((nsIWidget *)parentWidget, // Parent nsIWidget
+                       nullptr,                   // Native parent widget
+                       deskRect,                  // Widget dimensions
+                       &widgetInitData);          // Widget initialization data
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  LayoutDeviceIntRect r = mWindow->GetClientBounds();
+  // Match the default background color of content. Important on windows
+  // since we no longer use content child widgets.
+  mWindow->SetBackgroundColor(NS_RGB(255,255,255));
+
+  // Create web shell
+  mDocShell = do_CreateInstance("@mozilla.org/docshell;1");
+  NS_ENSURE_TRUE(mDocShell, NS_ERROR_FAILURE);
+
+  mDocShell->SetOpener(aOpeningTab);
+
+  // Make sure to set the item type on the docshell _before_ calling
+  // Create() so it knows what type it is.
+  nsCOMPtr<nsIDocShellTreeItem> docShellAsItem(do_QueryInterface(mDocShell));
+  NS_ENSURE_TRUE(docShellAsItem, NS_ERROR_FAILURE);
+  NS_ENSURE_SUCCESS(EnsureChromeTreeOwner(), NS_ERROR_FAILURE);
+
+  docShellAsItem->SetTreeOwner(mChromeTreeOwner);
+  docShellAsItem->SetItemType(nsIDocShellTreeItem::typeChrome);
+
+  r.x = r.y = 0;
+  nsCOMPtr<nsIBaseWindow> docShellAsWin(do_QueryInterface(mDocShell));
+  NS_ENSURE_SUCCESS(docShellAsWin->InitWindow(nullptr, mWindow, 
+   r.x, r.y, r.width, r.height), NS_ERROR_FAILURE);
+  NS_ENSURE_SUCCESS(docShellAsWin->Create(), NS_ERROR_FAILURE);
+
+  // Attach a WebProgress listener.during initialization...
+  nsCOMPtr<nsIWebProgress> webProgress(do_GetInterface(mDocShell, &rv));
+  if (webProgress) {
+    webProgress->AddProgressListener(this, nsIWebProgress::NOTIFY_STATE_NETWORK);
+  }
+
+  if (aOpenerWindow) {
+    nsPIDOMWindowOuter* window = mDocShell->GetWindow();
+    MOZ_ASSERT(window);
+    window->SetOpenerWindow(nsPIDOMWindowOuter::From(aOpenerWindow), true);
+  }
+
+  // Eagerly create an about:blank content viewer with the right principal here,
+  // rather than letting it happening in the upcoming call to
+  // SetInitialPrincipalToSubject. This avoids creating the about:blank document
+  // and then blowing it away with a second one, which can cause problems for the
+  // top-level chrome window case. See bug 789773.
+  // Note that we don't accept expanded principals here, similar to
+  // SetInitialPrincipalToSubject.
+  if (nsContentUtils::IsInitialized()) { // Sometimes this happens really early  See bug 793370.
+    MOZ_ASSERT(mDocShell->ItemType() == nsIDocShellTreeItem::typeChrome);
+    nsCOMPtr<nsIPrincipal> principal = nsContentUtils::SubjectPrincipalOrSystemIfNativeCaller();
+    if (nsContentUtils::IsExpandedPrincipal(principal)) {
+      principal = nullptr;
+    }
+    rv = mDocShell->CreateAboutBlankContentViewer(principal);
+    NS_ENSURE_SUCCESS(rv, rv);
+    nsCOMPtr<nsIDocument> doc = mDocShell->GetDocument();
+    NS_ENSURE_TRUE(!!doc, NS_ERROR_FAILURE);
+    doc->SetIsInitialDocument(true);
+  }
+
+  if (nullptr != aUrl)  {
+    nsCString tmpStr;
+
+    rv = aUrl->GetSpec(tmpStr);
+    if (NS_FAILED(rv)) return rv;
+
+    NS_ConvertUTF8toUTF16 urlString(tmpStr);
+    nsCOMPtr<nsIWebNavigation> webNav(do_QueryInterface(mDocShell));
+    NS_ENSURE_TRUE(webNav, NS_ERROR_FAILURE);
+    rv = webNav->LoadURI(urlString.get(),
+                         nsIWebNavigation::LOAD_FLAGS_NONE,
+                         nullptr,
+                         nullptr,
+                         nullptr);
+    NS_ENSURE_SUCCESS(rv, rv);
+  }
+                     
+  return rv;
+}
+
+nsIPresShell*
+nsWebShellWindow::GetPresShell()
+{
+  if (!mDocShell)
+    return nullptr;
+
+  return mDocShell->GetPresShell();
+}
+
+bool
+nsWebShellWindow::WindowMoved(nsIWidget* aWidget, int32_t x, int32_t y)
+{
+  nsXULPopupManager* pm = nsXULPopupManager::GetInstance();
+  if (pm) {
+    nsCOMPtr<nsPIDOMWindowOuter> window =
+      mDocShell ? mDocShell->GetWindow() : nullptr;
+    pm->AdjustPopupsOnWindowChange(window);
+  }
+
+  // Notify all tabs that the widget moved.
+  if (mDocShell && mDocShell->GetWindow()) {
+    nsCOMPtr<EventTarget> eventTarget = mDocShell->GetWindow()->GetTopWindowRoot();
+    nsContentUtils::DispatchChromeEvent(mDocShell->GetDocument(),
+                                        eventTarget,
+                                        NS_LITERAL_STRING("MozUpdateWindowPos"),
+                                        false, false, nullptr);
+  }
+
+  // Persist position, but not immediately, in case this OS is firing
+  // repeated move events as the user drags the window
+  SetPersistenceTimer(PAD_POSITION);
+  return false;
+}
+
+bool
+nsWebShellWindow::WindowResized(nsIWidget* aWidget, int32_t aWidth, int32_t aHeight)
+{
+  nsCOMPtr<nsIBaseWindow> shellAsWin(do_QueryInterface(mDocShell));
+  if (shellAsWin) {
+    shellAsWin->SetPositionAndSize(0, 0, aWidth, aHeight, 0);
+  }
+  // Persist size, but not immediately, in case this OS is firing
+  // repeated size events as the user drags the sizing handle
+  if (!IsLocked())
+    SetPersistenceTimer(PAD_POSITION | PAD_SIZE | PAD_MISC);
+  return true;
+}
+
+bool
+nsWebShellWindow::RequestWindowClose(nsIWidget* aWidget)
+{
+  // Maintain a reference to this as it is about to get destroyed.
+  nsCOMPtr<nsIXULWindow> xulWindow(this);
+
+  nsCOMPtr<nsPIDOMWindowOuter> window(mDocShell ? mDocShell->GetWindow() : nullptr);
+  nsCOMPtr<EventTarget> eventTarget = do_QueryInterface(window);
+
+  nsCOMPtr<nsIPresShell> presShell = mDocShell->GetPresShell();
+  if (!presShell) {
+    mozilla::DebugOnly<bool> dying;
+    MOZ_ASSERT(NS_SUCCEEDED(mDocShell->IsBeingDestroyed(&dying)) && dying,
+               "No presShell, but window is not being destroyed");
+  } else if (eventTarget) {
+    RefPtr<nsPresContext> presContext = presShell->GetPresContext();
+
+    nsEventStatus status = nsEventStatus_eIgnore;
+    WidgetMouseEvent event(true, eWindowClose, nullptr,
+                           WidgetMouseEvent::eReal);
+    if (NS_SUCCEEDED(eventTarget->DispatchDOMEvent(&event, nullptr, presContext, &status)) &&
+        status == nsEventStatus_eConsumeNoDefault)
+      return false;
+  }
+
+  Destroy();
+  return false;
+}
+
+void
+nsWebShellWindow::SizeModeChanged(nsSizeMode sizeMode)
+{
+  // An alwaysRaised (or higher) window will hide any newly opened normal
+  // browser windows, so here we just drop a raised window to the normal
+  // zlevel if it's maximized. We make no provision for automatically
+  // re-raising it when restored.
+  if (sizeMode == nsSizeMode_Maximized || sizeMode == nsSizeMode_Fullscreen) {
+    uint32_t zLevel;
+    GetZLevel(&zLevel);
+    if (zLevel > nsIXULWindow::normalZ)
+      SetZLevel(nsIXULWindow::normalZ);
+  }
+  mWindow->SetSizeMode(sizeMode);
+
+  // Persist mode, but not immediately, because in many (all?)
+  // cases this will merge with the similar call in NS_SIZE and
+  // write the attribute values only once.
+  SetPersistenceTimer(PAD_MISC);
+  nsCOMPtr<nsPIDOMWindowOuter> ourWindow =
+    mDocShell ? mDocShell->GetWindow() : nullptr;
+  if (ourWindow) {
+    MOZ_ASSERT(ourWindow->IsOuterWindow());
+
+    // Ensure that the fullscreen state is synchronized between
+    // the widget and the outer window object.
+    if (sizeMode == nsSizeMode_Fullscreen) {
+      ourWindow->SetFullScreen(true);
+    }
+    else if (sizeMode != nsSizeMode_Minimized) {
+      if (ourWindow->GetFullScreen()) {
+        // The first SetFullscreenInternal call below ensures that we do
+        // not trigger any fullscreen transition even if the window was
+        // put in fullscreen only for the Fullscreen API. The second
+        // SetFullScreen call ensures that the window really exit from
+        // fullscreen even if it entered fullscreen for both Fullscreen
+        // Mode and Fullscreen API.
+        ourWindow->SetFullscreenInternal(FullscreenReason::ForForceExitFullscreen, false);
+        ourWindow->SetFullScreen(false);
+      }
+    }
+
+    // And always fire a user-defined sizemodechange event on the window
+    ourWindow->DispatchCustomEvent(NS_LITERAL_STRING("sizemodechange"));
+  }
+
+  nsIPresShell* presShell;
+  if ((presShell = GetPresShell())) {
+    presShell->GetPresContext()->SizeModeChanged(sizeMode);
+  }
+
+  // Note the current implementation of SetSizeMode just stores
+  // the new state; it doesn't actually resize. So here we store
+  // the state and pass the event on to the OS. The day is coming
+  // when we'll handle the event here, and the return result will
+  // then need to be different.
+}
+
+void
+nsWebShellWindow::UIResolutionChanged()
+{
+  nsCOMPtr<nsPIDOMWindowOuter> ourWindow =
+    mDocShell ? mDocShell->GetWindow() : nullptr;
+  if (ourWindow) {
+    MOZ_ASSERT(ourWindow->IsOuterWindow());
+    ourWindow->DispatchCustomEvent(NS_LITERAL_STRING("resolutionchange"));
+  }
+}
+
+void
+nsWebShellWindow::FullscreenChanged(bool aInFullscreen)
+{
+  if (mDocShell) {
+    if (nsCOMPtr<nsPIDOMWindowOuter> ourWindow = mDocShell->GetWindow()) {
+      ourWindow->FinishFullscreenChange(aInFullscreen);
+    }
+  }
+}
+
+void
+nsWebShellWindow::OSToolbarButtonPressed()
+{
+  // Keep a reference as setting the chrome flags can fire events.
+  nsCOMPtr<nsIXULWindow> xulWindow(this);
+
+  // rjc: don't use "nsIWebBrowserChrome::CHROME_EXTRA"
+  //      due to components with multiple sidebar components
+  //      (such as Mail/News, Addressbook, etc)... and frankly,
+  //      Mac IE, OmniWeb, and other Mac OS X apps all work this way
+  uint32_t    chromeMask = (nsIWebBrowserChrome::CHROME_TOOLBAR |
+                            nsIWebBrowserChrome::CHROME_LOCATIONBAR |
+                            nsIWebBrowserChrome::CHROME_PERSONAL_TOOLBAR);
+
+  nsCOMPtr<nsIWebBrowserChrome> wbc(do_GetInterface(xulWindow));
+  if (!wbc)
+    return;
+
+  uint32_t    chromeFlags, newChromeFlags = 0;
+  wbc->GetChromeFlags(&chromeFlags);
+  newChromeFlags = chromeFlags & chromeMask;
+  if (!newChromeFlags)    chromeFlags |= chromeMask;
+  else                    chromeFlags &= (~newChromeFlags);
+  wbc->SetChromeFlags(chromeFlags);
+}
+
+bool
+nsWebShellWindow::ZLevelChanged(bool aImmediate, nsWindowZ *aPlacement,
+                                nsIWidget* aRequestBelow, nsIWidget** aActualBelow)
+{
+  if (aActualBelow)
+    *aActualBelow = nullptr;
+
+  return ConstrainToZLevel(aImmediate, aPlacement, aRequestBelow, aActualBelow);
+}
+
+void
+nsWebShellWindow::WindowActivated()
+{
+  nsCOMPtr<nsIXULWindow> xulWindow(this);
+
+  // focusing the window could cause it to close, so keep a reference to it
+  nsCOMPtr<nsPIDOMWindowOuter> window = mDocShell ? mDocShell->GetWindow() : nullptr;
+  nsCOMPtr<nsIFocusManager> fm = do_GetService(FOCUSMANAGER_CONTRACTID);
+  if (fm && window)
+    fm->WindowRaised(window);
+
+  if (mChromeLoaded) {
+    PersistentAttributesDirty(PAD_POSITION | PAD_SIZE | PAD_MISC);
+    SavePersistentAttributes();
+   }
+}
+
+void
+nsWebShellWindow::WindowDeactivated()
+{
+  nsCOMPtr<nsIXULWindow> xulWindow(this);
+
+  nsCOMPtr<nsPIDOMWindowOuter> window =
+    mDocShell ? mDocShell->GetWindow() : nullptr;
+  nsCOMPtr<nsIFocusManager> fm = do_GetService(FOCUSMANAGER_CONTRACTID);
+  if (fm && window)
+    fm->WindowLowered(window);
+}
+
+#ifdef USE_NATIVE_MENUS
+static void LoadNativeMenus(nsIDOMDocument *aDOMDoc, nsIWidget *aParentWindow)
+{
+  nsCOMPtr<nsINativeMenuService> nms = do_GetService("@mozilla.org/widget/nativemenuservice;1");
+  if (!nms) {
+    return;
+  }
+
+  // Find the menubar tag (if there is more than one, we ignore all but
+  // the first).
+  nsCOMPtr<nsIDOMNodeList> menubarElements;
+  aDOMDoc->GetElementsByTagNameNS(NS_LITERAL_STRING("http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul"),
+                                  NS_LITERAL_STRING("menubar"),
+                                  getter_AddRefs(menubarElements));
+
+  nsCOMPtr<nsIDOMNode> menubarNode;
+  if (menubarElements)
+    menubarElements->Item(0, getter_AddRefs(menubarNode));
+
+  if (menubarNode) {
+    nsCOMPtr<nsIContent> menubarContent(do_QueryInterface(menubarNode));
+    nms->CreateNativeMenuBar(aParentWindow, menubarContent);
+  } else {
+    nms->CreateNativeMenuBar(aParentWindow, nullptr);
+  }
+}
+#endif
+
+namespace mozilla {
+
+class WebShellWindowTimerCallback final : public nsITimerCallback
+{
+public:
+  explicit WebShellWindowTimerCallback(nsWebShellWindow* aWindow)
+    : mWindow(aWindow)
+  {}
+
+  NS_DECL_THREADSAFE_ISUPPORTS
+
+  NS_IMETHOD Notify(nsITimer* aTimer) override
+  {
+    // Although this object participates in a refcount cycle (this -> mWindow
+    // -> mSPTimer -> this), mSPTimer is a one-shot timer and releases this
+    // after it fires.  So we don't need to release mWindow here.
+
+    mWindow->FirePersistenceTimer();
+    return NS_OK;
+  }
+
+private:
+  ~WebShellWindowTimerCallback() {}
+
+  RefPtr<nsWebShellWindow> mWindow;
+};
+
+NS_IMPL_ISUPPORTS(WebShellWindowTimerCallback, nsITimerCallback)
+
+} // namespace mozilla
+
+void
+nsWebShellWindow::SetPersistenceTimer(uint32_t aDirtyFlags)
+{
+  MutexAutoLock lock(mSPTimerLock);
+  if (!mSPTimer) {
+    mSPTimer = do_CreateInstance("@mozilla.org/timer;1");
+    if (!mSPTimer) {
+      NS_WARNING("Couldn't create @mozilla.org/timer;1 instance?");
+      return;
+    }
+  }
+
+  RefPtr<WebShellWindowTimerCallback> callback =
+    new WebShellWindowTimerCallback(this);
+  mSPTimer->InitWithCallback(callback, SIZE_PERSISTENCE_TIMEOUT,
+                             nsITimer::TYPE_ONE_SHOT);
+
+  PersistentAttributesDirty(aDirtyFlags);
+}
+
+void
+nsWebShellWindow::FirePersistenceTimer()
+{
+  MutexAutoLock lock(mSPTimerLock);
+  SavePersistentAttributes();
+}
+
+
+//----------------------------------------
+// nsIWebProgessListener implementation
+//----------------------------------------
+NS_IMETHODIMP
+nsWebShellWindow::OnProgressChange(nsIWebProgress *aProgress,
+                                   nsIRequest *aRequest,
+                                   int32_t aCurSelfProgress,
+                                   int32_t aMaxSelfProgress,
+                                   int32_t aCurTotalProgress,
+                                   int32_t aMaxTotalProgress)
+{
+  NS_NOTREACHED("notification excluded in AddProgressListener(...)");
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWebShellWindow::OnStateChange(nsIWebProgress *aProgress,
+                                nsIRequest *aRequest,
+                                uint32_t aStateFlags,
+                                nsresult aStatus)
+{
+  // If the notification is not about a document finishing, then just
+  // ignore it...
+  if (!(aStateFlags & nsIWebProgressListener::STATE_STOP) || 
+      !(aStateFlags & nsIWebProgressListener::STATE_IS_NETWORK)) {
+    return NS_OK;
+  }
+
+  if (mChromeLoaded)
+    return NS_OK;
+
+  // If this document notification is for a frame then ignore it...
+  nsCOMPtr<mozIDOMWindowProxy> eventWin;
+  aProgress->GetDOMWindow(getter_AddRefs(eventWin));
+  auto* eventPWin = nsPIDOMWindowOuter::From(eventWin);
+  if (eventPWin) {
+    nsPIDOMWindowOuter *rootPWin = eventPWin->GetPrivateRoot();
+    if (eventPWin != rootPWin)
+      return NS_OK;
+  }
+
+  mChromeLoaded = true;
+  mLockedUntilChromeLoad = false;
+
+#ifdef USE_NATIVE_MENUS
+  ///////////////////////////////
+  // Find the Menubar DOM  and Load the menus, hooking them up to the loaded commands
+  ///////////////////////////////
+  nsCOMPtr<nsIContentViewer> cv;
+  mDocShell->GetContentViewer(getter_AddRefs(cv));
+  if (cv) {
+    nsCOMPtr<nsIDOMDocument> menubarDOMDoc(do_QueryInterface(cv->GetDocument()));
+    if (menubarDOMDoc)
+      LoadNativeMenus(menubarDOMDoc, mWindow);
+  }
+#endif // USE_NATIVE_MENUS
+
+  OnChromeLoaded();
+  LoadContentAreas();
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWebShellWindow::OnLocationChange(nsIWebProgress *aProgress,
+                                   nsIRequest *aRequest,
+                                   nsIURI *aURI,
+                                   uint32_t aFlags)
+{
+  NS_NOTREACHED("notification excluded in AddProgressListener(...)");
+  return NS_OK;
+}
+
+NS_IMETHODIMP 
+nsWebShellWindow::OnStatusChange(nsIWebProgress* aWebProgress,
+                                 nsIRequest* aRequest,
+                                 nsresult aStatus,
+                                 const char16_t* aMessage)
+{
+  NS_NOTREACHED("notification excluded in AddProgressListener(...)");
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWebShellWindow::OnSecurityChange(nsIWebProgress *aWebProgress,
+                                   nsIRequest *aRequest,
+                                   uint32_t state)
+{
+  NS_NOTREACHED("notification excluded in AddProgressListener(...)");
+  return NS_OK;
+}
+
+
+//----------------------------------------
+
+// if the main document URL specified URLs for any content areas, start them loading
+void nsWebShellWindow::LoadContentAreas() {
+
+  nsAutoString searchSpec;
+
+  // fetch the chrome document URL
+  nsCOMPtr<nsIContentViewer> contentViewer;
+  // yes, it's possible for the docshell to be null even this early
+  // see bug 57514.
+  if (mDocShell)
+    mDocShell->GetContentViewer(getter_AddRefs(contentViewer));
+  if (contentViewer) {
+    nsIDocument* doc = contentViewer->GetDocument();
+    if (doc) {
+      nsIURI* mainURL = doc->GetDocumentURI();
+
+      nsCOMPtr<nsIURL> url = do_QueryInterface(mainURL);
+      if (url) {
+        nsAutoCString search;
+        url->GetQuery(search);
+
+        AppendUTF8toUTF16(search, searchSpec);
+      }
+    }
+  }
+
+  // content URLs are specified in the search part of the URL
+  // as <contentareaID>=<escapedURL>[;(repeat)]
+  if (!searchSpec.IsEmpty()) {
+    int32_t     begPos,
+                eqPos,
+                endPos;
+    nsString    contentAreaID,
+                contentURL;
+    char        *urlChar;
+    nsresult rv;
+    for (endPos = 0; endPos < (int32_t)searchSpec.Length(); ) {
+      // extract contentAreaID and URL substrings
+      begPos = endPos;
+      eqPos = searchSpec.FindChar('=', begPos);
+      if (eqPos < 0)
+        break;
+
+      endPos = searchSpec.FindChar(';', eqPos);
+      if (endPos < 0)
+        endPos = searchSpec.Length();
+      searchSpec.Mid(contentAreaID, begPos, eqPos-begPos);
+      searchSpec.Mid(contentURL, eqPos+1, endPos-eqPos-1);
+      endPos++;
+
+      // see if we have a docshell with a matching contentAreaID
+      nsCOMPtr<nsIDocShellTreeItem> content;
+      rv = GetContentShellById(contentAreaID.get(), getter_AddRefs(content));
+      if (NS_SUCCEEDED(rv) && content) {
+        nsCOMPtr<nsIWebNavigation> webNav(do_QueryInterface(content));
+        if (webNav) {
+          urlChar = ToNewCString(contentURL);
+          if (urlChar) {
+            nsUnescape(urlChar);
+            contentURL.AssignWithConversion(urlChar);
+            webNav->LoadURI(contentURL.get(),
+                          nsIWebNavigation::LOAD_FLAGS_NONE,
+                          nullptr,
+                          nullptr,
+                          nullptr);
+            free(urlChar);
+          }
+        }
+      }
+    }
+  }
+}
+
+/**
+ * ExecuteCloseHandler - Run the close handler, if any.
+ * @return true iff we found a close handler to run.
+ */
+bool nsWebShellWindow::ExecuteCloseHandler()
+{
+  /* If the event handler closes this window -- a likely scenario --
+     things get deleted out of order without this death grip.
+     (The problem may be the death grip in nsWindow::windowProc,
+     which forces this window's widget to remain alive longer
+     than it otherwise would.) */
+  nsCOMPtr<nsIXULWindow> kungFuDeathGrip(this);
+
+  nsCOMPtr<EventTarget> eventTarget;
+  if (mDocShell) {
+    eventTarget = do_QueryInterface(mDocShell->GetWindow());
+  }
+
+  if (eventTarget) {
+    nsCOMPtr<nsIContentViewer> contentViewer;
+    mDocShell->GetContentViewer(getter_AddRefs(contentViewer));
+    if (contentViewer) {
+      RefPtr<nsPresContext> presContext;
+      contentViewer->GetPresContext(getter_AddRefs(presContext));
+
+      nsEventStatus status = nsEventStatus_eIgnore;
+      WidgetMouseEvent event(true, eWindowClose, nullptr,
+                             WidgetMouseEvent::eReal);
+
+      nsresult rv =
+        eventTarget->DispatchDOMEvent(&event, nullptr, presContext, &status);
+      if (NS_SUCCEEDED(rv) && status == nsEventStatus_eConsumeNoDefault)
+        return true;
+      // else fall through and return false
+    }
+  }
+
+  return false;
+} // ExecuteCloseHandler
+
+void nsWebShellWindow::ConstrainToOpenerScreen(int32_t* aX, int32_t* aY)
+{
+  if (mOpenerScreenRect.IsEmpty()) {
+    *aX = *aY = 0;
+    return;
+  }
+
+  int32_t left, top, width, height;
+  // Constrain initial positions to the same screen as opener
+  nsCOMPtr<nsIScreenManager> screenmgr = do_GetService("@mozilla.org/gfx/screenmanager;1");
+  if (screenmgr) {
+    nsCOMPtr<nsIScreen> screen;
+    screenmgr->ScreenForRect(mOpenerScreenRect.x, mOpenerScreenRect.y,
+                             mOpenerScreenRect.width, mOpenerScreenRect.height,
+                             getter_AddRefs(screen));
+    if (screen) {
+      screen->GetAvailRectDisplayPix(&left, &top, &width, &height);
+      if (*aX < left || *aX > left + width) {
+        *aX = left;
+      }
+      if (*aY < top || *aY > top + height) {
+        *aY = top;
+      }
+    }
+  }
+}
+
+// nsIBaseWindow
+NS_IMETHODIMP nsWebShellWindow::Destroy()
+{
+  nsresult rv;
+  nsCOMPtr<nsIWebProgress> webProgress(do_GetInterface(mDocShell, &rv));
+  if (webProgress) {
+    webProgress->RemoveProgressListener(this);
+  }
+
+  nsCOMPtr<nsIXULWindow> kungFuDeathGrip(this);
+  {
+    MutexAutoLock lock(mSPTimerLock);
+    if (mSPTimer) {
+      mSPTimer->Cancel();
+      SavePersistentAttributes();
+      mSPTimer = nullptr;
+    }
+  }
+  return nsXULWindow::Destroy();
+}
+
+nsIXULWindow*
+nsWebShellWindow::WidgetListenerDelegate::GetXULWindow()
+{
+  return mWebShellWindow->GetXULWindow();
+}
+
+nsIPresShell*
+nsWebShellWindow::WidgetListenerDelegate::GetPresShell()
+{
+  return mWebShellWindow->GetPresShell();
+}
+
+bool
+nsWebShellWindow::WidgetListenerDelegate::WindowMoved(
+  nsIWidget* aWidget, int32_t aX, int32_t aY)
+{
+  RefPtr<nsWebShellWindow> holder = mWebShellWindow;
+  return holder->WindowMoved(aWidget, aX, aY);
+}
+
+bool
+nsWebShellWindow::WidgetListenerDelegate::WindowResized(
+  nsIWidget* aWidget, int32_t aWidth, int32_t aHeight)
+{
+  RefPtr<nsWebShellWindow> holder = mWebShellWindow;
+  return holder->WindowResized(aWidget, aWidth, aHeight);
+}
+
+bool
+nsWebShellWindow::WidgetListenerDelegate::RequestWindowClose(nsIWidget* aWidget)
+{
+  RefPtr<nsWebShellWindow> holder = mWebShellWindow;
+  return holder->RequestWindowClose(aWidget);
+}
+
+void
+nsWebShellWindow::WidgetListenerDelegate::SizeModeChanged(nsSizeMode aSizeMode)
+{
+  RefPtr<nsWebShellWindow> holder = mWebShellWindow;
+  holder->SizeModeChanged(aSizeMode);
+}
+
+void
+nsWebShellWindow::WidgetListenerDelegate::UIResolutionChanged()
+{
+  RefPtr<nsWebShellWindow> holder = mWebShellWindow;
+  holder->UIResolutionChanged();
+}
+
+void
+nsWebShellWindow::WidgetListenerDelegate::FullscreenChanged(bool aInFullscreen)
+{
+  RefPtr<nsWebShellWindow> holder = mWebShellWindow;
+  holder->FullscreenChanged(aInFullscreen);
+}
+
+void
+nsWebShellWindow::WidgetListenerDelegate::OSToolbarButtonPressed()
+{
+  RefPtr<nsWebShellWindow> holder = mWebShellWindow;
+  holder->OSToolbarButtonPressed();
+}
+
+bool
+nsWebShellWindow::WidgetListenerDelegate::ZLevelChanged(
+  bool aImmediate, nsWindowZ *aPlacement, nsIWidget* aRequestBelow,
+  nsIWidget** aActualBelow)
+{
+  RefPtr<nsWebShellWindow> holder = mWebShellWindow;
+  return holder->ZLevelChanged(aImmediate,
+                               aPlacement,
+                               aRequestBelow,
+                               aActualBelow);
+}
+
+void
+nsWebShellWindow::WidgetListenerDelegate::WindowActivated()
+{
+  RefPtr<nsWebShellWindow> holder = mWebShellWindow;
+  holder->WindowActivated();
+}
+
+void
+nsWebShellWindow::WidgetListenerDelegate::WindowDeactivated()
+{
+  RefPtr<nsWebShellWindow> holder = mWebShellWindow;
+  holder->WindowDeactivated();
+}
diff --git a/xpfe/appshell/nsWebShellWindow.h b/xpfe/appshell/nsWebShellWindow.h
new file mode 100644
index 000000000..e2b796161
--- /dev/null
+++ b/xpfe/appshell/nsWebShellWindow.h
@@ -0,0 +1,116 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsWebShellWindow_h__
+#define nsWebShellWindow_h__
+
+#include "mozilla/Mutex.h"
+#include "nsIWebProgressListener.h"
+#include "nsITimer.h"
+#include "nsCOMPtr.h"
+#include "nsXULWindow.h"
+#include "nsIWidgetListener.h"
+#include "nsITabParent.h"
+
+/* Forward declarations.... */
+class nsIURI;
+
+struct nsWidgetInitData;
+
+namespace mozilla {
+class WebShellWindowTimerCallback;
+} // namespace mozilla
+
+class nsWebShellWindow final : public nsXULWindow,
+                               public nsIWebProgressListener
+{
+public:
+
+  // The implementation of non-refcounted nsIWidgetListener, which would hold a
+  // strong reference on stack before calling nsWebShellWindow
+  class WidgetListenerDelegate : public nsIWidgetListener
+  {
+  public:
+    explicit WidgetListenerDelegate(nsWebShellWindow* aWebShellWindow)
+      : mWebShellWindow(aWebShellWindow) {}
+
+    virtual nsIXULWindow* GetXULWindow() override;
+    virtual nsIPresShell* GetPresShell() override;
+    virtual bool WindowMoved(nsIWidget* aWidget, int32_t x, int32_t y) override;
+    virtual bool WindowResized(nsIWidget* aWidget, int32_t aWidth, int32_t aHeight) override;
+    virtual bool RequestWindowClose(nsIWidget* aWidget) override;
+    virtual void SizeModeChanged(nsSizeMode sizeMode) override;
+    virtual void UIResolutionChanged() override;
+    virtual void FullscreenChanged(bool aInFullscreen) override;
+    virtual void OSToolbarButtonPressed() override;
+    virtual bool ZLevelChanged(bool aImmediate,
+                               nsWindowZ *aPlacement,
+                               nsIWidget* aRequestBelow,
+                               nsIWidget** aActualBelow) override;
+    virtual void WindowActivated() override;
+    virtual void WindowDeactivated() override;
+
+  private:
+    // The lifetime of WidgetListenerDelegate is bound to nsWebShellWindow so
+    // we just use a raw pointer here.
+    nsWebShellWindow* mWebShellWindow;
+  };
+
+  explicit nsWebShellWindow(uint32_t aChromeFlags);
+
+  // nsISupports interface...
+  NS_DECL_ISUPPORTS_INHERITED
+
+  // nsWebShellWindow methods...
+  nsresult Initialize(nsIXULWindow * aParent, nsIXULWindow * aOpener,
+                      nsIURI* aUrl,
+                      int32_t aInitialWidth, int32_t aInitialHeight,
+                      bool aIsHiddenWindow,
+                      nsITabParent *aOpeningTab,
+                      mozIDOMWindowProxy *aOpenerWIndow,
+                      nsWidgetInitData& widgetInitData);
+
+  nsresult Toolbar();
+
+  // nsIWebProgressListener
+  NS_DECL_NSIWEBPROGRESSLISTENER
+
+  // nsIBaseWindow
+  NS_IMETHOD Destroy() override;
+
+  // nsIWidgetListener
+  nsIXULWindow* GetXULWindow() { return this; }
+  nsIPresShell* GetPresShell();
+  bool WindowMoved(nsIWidget* aWidget, int32_t x, int32_t y);
+  bool WindowResized(nsIWidget* aWidget, int32_t aWidth, int32_t aHeight);
+  bool RequestWindowClose(nsIWidget* aWidget);
+  void SizeModeChanged(nsSizeMode sizeMode);
+  void UIResolutionChanged();
+  void FullscreenChanged(bool aInFullscreen);
+  void OSToolbarButtonPressed();
+  bool ZLevelChanged(bool aImmediate, nsWindowZ *aPlacement,
+                     nsIWidget* aRequestBelow, nsIWidget** aActualBelow);
+  void WindowActivated();
+  void WindowDeactivated();
+
+protected:
+  friend class mozilla::WebShellWindowTimerCallback;
+  
+  virtual ~nsWebShellWindow();
+
+  void                     LoadContentAreas();
+  bool                     ExecuteCloseHandler();
+  void                     ConstrainToOpenerScreen(int32_t* aX, int32_t* aY);
+
+  nsCOMPtr<nsITimer>      mSPTimer;
+  mozilla::Mutex          mSPTimerLock;
+  WidgetListenerDelegate  mWidgetListenerDelegate;
+
+  void        SetPersistenceTimer(uint32_t aDirtyFlags);
+  void        FirePersistenceTimer();
+};
+
+
+#endif /* nsWebShellWindow_h__ */
diff --git a/xpfe/appshell/nsWindowMediator.cpp b/xpfe/appshell/nsWindowMediator.cpp
new file mode 100644
index 000000000..6d69bc764
--- /dev/null
+++ b/xpfe/appshell/nsWindowMediator.cpp
@@ -0,0 +1,846 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "nsCOMPtr.h"
+#include "nsString.h"
+#include "nsReadableUtils.h"
+#include "nsUnicharUtils.h"
+#include "nsTArray.h"
+#include "nsIBaseWindow.h"
+#include "nsIWidget.h"
+#include "nsIDOMWindow.h"
+#include "nsIObserverService.h"
+#include "nsIServiceManager.h"
+#include "nsISimpleEnumerator.h"
+#include "nsAppShellWindowEnumerator.h"
+#include "nsWindowMediator.h"
+#include "nsIWindowMediatorListener.h"
+#include "nsXPIDLString.h"
+#include "nsGlobalWindow.h"
+
+#include "nsIDocShell.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsIXULWindow.h"
+
+using namespace mozilla;
+
+static bool notifyOpenWindow(nsIWindowMediatorListener *aElement, void* aData);
+static bool notifyCloseWindow(nsIWindowMediatorListener *aElement, void* aData);
+static bool notifyWindowTitleChange(nsIWindowMediatorListener *aElement, void* aData);
+
+// for notifyWindowTitleChange
+struct WindowTitleData {
+  nsIXULWindow* mWindow;
+  const char16_t *mTitle;
+};
+
+nsresult
+nsWindowMediator::GetDOMWindow(nsIXULWindow* inWindow,
+                               nsCOMPtr<nsPIDOMWindowOuter>& outDOMWindow)
+{
+  nsCOMPtr<nsIDocShell> docShell;
+
+  outDOMWindow = nullptr;
+  inWindow->GetDocShell(getter_AddRefs(docShell));
+  NS_ENSURE_TRUE(docShell, NS_ERROR_FAILURE);
+
+  outDOMWindow = docShell->GetWindow();
+  return outDOMWindow ? NS_OK : NS_ERROR_FAILURE;
+}
+
+nsWindowMediator::nsWindowMediator() :
+  mEnumeratorList(), mOldestWindow(nullptr), mTopmostWindow(nullptr),
+  mTimeStamp(0), mSortingZOrder(false), mReady(false)
+{
+}
+
+nsWindowMediator::~nsWindowMediator()
+{
+  while (mOldestWindow)
+    UnregisterWindow(mOldestWindow);
+}
+
+nsresult nsWindowMediator::Init()
+{
+  nsresult rv;
+  nsCOMPtr<nsIObserverService> obsSvc =
+    do_GetService("@mozilla.org/observer-service;1", &rv);
+  NS_ENSURE_SUCCESS(rv, rv);
+  rv = obsSvc->AddObserver(this, "xpcom-shutdown", true);
+  NS_ENSURE_SUCCESS(rv, rv);
+
+  mReady = true;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsWindowMediator::RegisterWindow(nsIXULWindow* inWindow)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_STATE(mReady);
+
+  if (GetInfoFor(inWindow)) {
+    NS_ERROR("multiple window registration");
+    return NS_ERROR_FAILURE;
+  }
+
+  mTimeStamp++;
+
+  // Create window info struct and add to list of windows
+  nsWindowInfo* windowInfo = new nsWindowInfo(inWindow, mTimeStamp);
+
+  WindowTitleData winData = { inWindow, nullptr };
+  mListeners.EnumerateForwards(notifyOpenWindow, &winData);
+  
+  if (mOldestWindow)
+    windowInfo->InsertAfter(mOldestWindow->mOlder, nullptr);
+  else
+    mOldestWindow = windowInfo;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::UnregisterWindow(nsIXULWindow* inWindow)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_STATE(mReady);
+  nsWindowInfo *info = GetInfoFor(inWindow);
+  if (info)
+    return UnregisterWindow(info);
+  return NS_ERROR_INVALID_ARG;
+}
+
+nsresult
+nsWindowMediator::UnregisterWindow(nsWindowInfo *inInfo)
+{
+  // Inform the iterators
+  uint32_t index = 0;
+  while (index < mEnumeratorList.Length()) {
+    mEnumeratorList[index]->WindowRemoved(inInfo);
+    index++;
+  }
+  
+  WindowTitleData winData = { inInfo->mWindow.get(), nullptr };
+  mListeners.EnumerateForwards(notifyCloseWindow, &winData);
+
+  // Remove from the lists and free up 
+  if (inInfo == mOldestWindow)
+    mOldestWindow = inInfo->mYounger;
+  if (inInfo == mTopmostWindow)
+    mTopmostWindow = inInfo->mLower;
+  inInfo->Unlink(true, true);
+  if (inInfo == mOldestWindow)
+    mOldestWindow = nullptr;
+  if (inInfo == mTopmostWindow)
+    mTopmostWindow = nullptr;
+  delete inInfo;  
+
+  return NS_OK;
+}
+
+nsWindowInfo*
+nsWindowMediator::GetInfoFor(nsIXULWindow *aWindow)
+{
+  nsWindowInfo *info,
+               *listEnd;
+
+  if (!aWindow)
+    return nullptr;
+
+  info = mOldestWindow;
+  listEnd = nullptr;
+  while (info != listEnd) {
+    if (info->mWindow.get() == aWindow)
+      return info;
+    info = info->mYounger;
+    listEnd = mOldestWindow;
+  }
+  return nullptr;
+}
+
+nsWindowInfo*
+nsWindowMediator::GetInfoFor(nsIWidget *aWindow)
+{
+  nsWindowInfo *info,
+               *listEnd;
+
+  if (!aWindow)
+    return nullptr;
+
+  info = mOldestWindow;
+  listEnd = nullptr;
+
+  nsCOMPtr<nsIWidget> scanWidget;
+  while (info != listEnd) {
+    nsCOMPtr<nsIBaseWindow> base(do_QueryInterface(info->mWindow));
+    if (base)
+      base->GetMainWidget(getter_AddRefs(scanWidget));
+    if (aWindow == scanWidget.get())
+      return info;
+    info = info->mYounger;
+    listEnd = mOldestWindow;
+  }
+  return nullptr;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::GetEnumerator(const char16_t* inType, nsISimpleEnumerator** outEnumerator)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_ARG_POINTER(outEnumerator);
+  NS_ENSURE_STATE(mReady);
+
+  RefPtr<nsAppShellWindowEnumerator> enumerator = new nsASDOMWindowEarlyToLateEnumerator(inType, *this);
+  enumerator.forget(outEnumerator);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::GetXULWindowEnumerator(const char16_t* inType, nsISimpleEnumerator** outEnumerator)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_ARG_POINTER(outEnumerator);
+  NS_ENSURE_STATE(mReady);
+
+  RefPtr<nsAppShellWindowEnumerator> enumerator = new nsASXULWindowEarlyToLateEnumerator(inType, *this);
+  enumerator.forget(outEnumerator);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::GetZOrderDOMWindowEnumerator(
+            const char16_t *aWindowType, bool aFrontToBack,
+            nsISimpleEnumerator **_retval)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_ARG_POINTER(_retval);
+  NS_ENSURE_STATE(mReady);
+
+  RefPtr<nsAppShellWindowEnumerator> enumerator;
+  if (aFrontToBack)
+    enumerator = new nsASDOMWindowFrontToBackEnumerator(aWindowType, *this);
+  else
+    enumerator = new nsASDOMWindowBackToFrontEnumerator(aWindowType, *this);
+
+  enumerator.forget(_retval);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::GetZOrderXULWindowEnumerator(
+            const char16_t *aWindowType, bool aFrontToBack,
+            nsISimpleEnumerator **_retval)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_ARG_POINTER(_retval);
+  NS_ENSURE_STATE(mReady);
+
+  RefPtr<nsAppShellWindowEnumerator> enumerator;
+  if (aFrontToBack)
+    enumerator = new nsASXULWindowFrontToBackEnumerator(aWindowType, *this);
+  else
+    enumerator = new nsASXULWindowBackToFrontEnumerator(aWindowType, *this);
+
+  enumerator.forget(_retval);
+  return NS_OK;
+}
+
+int32_t
+nsWindowMediator::AddEnumerator(nsAppShellWindowEnumerator * inEnumerator)
+{
+  return mEnumeratorList.AppendElement(inEnumerator) != nullptr;
+}
+
+int32_t
+nsWindowMediator::RemoveEnumerator(nsAppShellWindowEnumerator * inEnumerator)
+{
+  return mEnumeratorList.RemoveElement(inEnumerator);
+}
+
+// Returns the window of type inType ( if null return any window type ) which has the most recent
+// time stamp
+NS_IMETHODIMP
+nsWindowMediator::GetMostRecentWindow(const char16_t* inType,
+                                      mozIDOMWindowProxy** outWindow)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_ARG_POINTER(outWindow);
+  *outWindow = nullptr;
+  if (!mReady)
+    return NS_OK;
+
+  // Find the most window with the highest time stamp that matches
+  // the requested type
+  nsWindowInfo* info = MostRecentWindowInfo(inType, false);
+  if (info && info->mWindow) {
+    nsCOMPtr<nsPIDOMWindowOuter> DOMWindow;
+    if (NS_SUCCEEDED(GetDOMWindow(info->mWindow, DOMWindow))) {  
+      DOMWindow.forget(outWindow);
+      return NS_OK;
+    }
+    return NS_ERROR_FAILURE;
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::GetMostRecentNonPBWindow(const char16_t* aType, mozIDOMWindowProxy** aWindow)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_ARG_POINTER(aWindow);
+  *aWindow = nullptr;
+
+  nsWindowInfo *info = MostRecentWindowInfo(aType, true);
+  nsCOMPtr<nsPIDOMWindowOuter> domWindow;
+  if (info && info->mWindow) {
+    GetDOMWindow(info->mWindow, domWindow);
+  }
+
+  if (!domWindow) {
+    return NS_ERROR_FAILURE;
+  }
+
+  domWindow.forget(aWindow);
+  return NS_OK;
+}
+
+nsWindowInfo*
+nsWindowMediator::MostRecentWindowInfo(const char16_t* inType,
+                                       bool aSkipPrivateBrowsingOrClosed)
+{
+  int32_t       lastTimeStamp = -1;
+  nsAutoString  typeString(inType);
+  bool          allWindows = !inType || typeString.IsEmpty();
+
+  // Find the most recent window with the highest time stamp that matches
+  // the requested type and has the correct browsing mode.
+  nsWindowInfo* searchInfo = mOldestWindow;
+  nsWindowInfo* listEnd = nullptr;
+  nsWindowInfo* foundInfo = nullptr;
+  for (; searchInfo != listEnd; searchInfo = searchInfo->mYounger) {
+    listEnd = mOldestWindow;
+
+    if (!allWindows && !searchInfo->TypeEquals(typeString)) {
+      continue;
+    }
+    if (searchInfo->mTimeStamp < lastTimeStamp) {
+      continue;
+    }
+    if (!searchInfo->mWindow) {
+      continue;
+    }
+    if (aSkipPrivateBrowsingOrClosed) {
+      nsCOMPtr<nsIDocShell> docShell;
+      searchInfo->mWindow->GetDocShell(getter_AddRefs(docShell));
+      nsCOMPtr<nsILoadContext> loadContext = do_QueryInterface(docShell);
+      if (!loadContext || loadContext->UsePrivateBrowsing()) {
+        continue;
+      }
+
+      nsCOMPtr<nsPIDOMWindowOuter> piwindow = docShell->GetWindow();
+      if (!piwindow || piwindow->Closed()) {
+        continue;
+      }
+    }
+
+    foundInfo = searchInfo;
+    lastTimeStamp = searchInfo->mTimeStamp;
+  }
+
+  return foundInfo;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::GetOuterWindowWithId(uint64_t aWindowID,
+                                       mozIDOMWindowProxy** aWindow)
+{
+  RefPtr<nsGlobalWindow> window = nsGlobalWindow::GetOuterWindowWithId(aWindowID);
+  nsCOMPtr<nsPIDOMWindowOuter> outer = window ? window->AsOuter() : nullptr;
+  outer.forget(aWindow);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::GetCurrentInnerWindowWithId(uint64_t aWindowID,
+                                              mozIDOMWindow** aWindow)
+{
+  RefPtr<nsGlobalWindow> window = nsGlobalWindow::GetInnerWindowWithId(aWindowID);
+
+  // not found
+  if (!window)
+    return NS_OK;
+
+  nsCOMPtr<nsPIDOMWindowInner> inner = window->AsInner();
+  nsCOMPtr<nsPIDOMWindowOuter> outer = inner->GetOuterWindow();
+  NS_ENSURE_TRUE(outer, NS_ERROR_UNEXPECTED);
+
+  // outer is already using another inner, so it's same as not found
+  if (outer->GetCurrentInnerWindow() != inner)
+    return NS_OK;
+
+  inner.forget(aWindow);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::UpdateWindowTimeStamp(nsIXULWindow* inWindow)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_STATE(mReady);
+  nsWindowInfo *info = GetInfoFor(inWindow);
+  if (info) {
+    // increment the window's time stamp
+    info->mTimeStamp = ++mTimeStamp;
+    return NS_OK;
+  }
+  return NS_ERROR_FAILURE; 
+}
+
+NS_IMETHODIMP
+nsWindowMediator::UpdateWindowTitle(nsIXULWindow* inWindow,
+                                    const char16_t* inTitle)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_STATE(mReady);
+  if (GetInfoFor(inWindow)) {
+    WindowTitleData winData = { inWindow, inTitle };
+    mListeners.EnumerateForwards(notifyWindowTitleChange, &winData);
+  }
+
+  return NS_OK;
+}
+
+/* This method's plan is to intervene only when absolutely necessary.
+   We will get requests to place our windows behind unknown windows.
+   For the most part, we need to leave those alone (turning them into
+   explicit requests to be on top breaks Windows.) So generally we
+   calculate a change as seldom as possible.
+*/
+NS_IMETHODIMP
+nsWindowMediator::CalculateZPosition(
+                nsIXULWindow   *inWindow,
+                uint32_t        inPosition,
+                nsIWidget      *inBelow,
+                uint32_t       *outPosition,
+                nsIWidget     **outBelow,
+                bool           *outAltered)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_ARG_POINTER(outBelow);
+  NS_ENSURE_STATE(mReady);
+
+  *outBelow = nullptr;
+
+  if (!inWindow || !outPosition || !outAltered)
+    return NS_ERROR_NULL_POINTER;
+
+  if (inPosition != nsIWindowMediator::zLevelTop &&
+      inPosition != nsIWindowMediator::zLevelBottom &&
+      inPosition != nsIWindowMediator::zLevelBelow)
+    return NS_ERROR_INVALID_ARG;
+
+  nsWindowInfo *info = mTopmostWindow;
+  nsIXULWindow *belowWindow = nullptr;
+  bool          found = false;
+  nsresult      result = NS_OK;
+
+  *outPosition = inPosition;
+  *outAltered = false;
+
+  if (mSortingZOrder) { // don't fight SortZOrder()
+    *outBelow = inBelow;
+    NS_IF_ADDREF(*outBelow);
+    return NS_OK;
+  }
+
+  uint32_t inZ;
+  GetZLevel(inWindow, &inZ);
+
+  if (inPosition == nsIWindowMediator::zLevelBelow) {
+    // locate inBelow. use topmost if it can't be found or isn't in the
+    // z-order list
+    info = GetInfoFor(inBelow);
+    if (!info || (info->mYounger != info && info->mLower == info))
+      info = mTopmostWindow;
+    else
+      found = true;
+
+    if (!found) {
+      /* Treat unknown windows as a request to be on top.
+         Not as it should be, but that's what Windows gives us.
+         Note we change inPosition, but not *outPosition. This forces
+         us to go through the "on top" calculation just below, without
+         necessarily changing the output parameters. */
+      inPosition = nsIWindowMediator::zLevelTop;
+    }
+  }
+
+  if (inPosition == nsIWindowMediator::zLevelTop) {
+    if (mTopmostWindow && mTopmostWindow->mZLevel > inZ) {
+      // asked for topmost, can't have it. locate highest allowed position.
+      do {
+        if (info->mZLevel <= inZ)
+          break;
+        info = info->mLower;
+      } while (info != mTopmostWindow);
+
+      *outPosition = nsIWindowMediator::zLevelBelow;
+      belowWindow = info->mHigher->mWindow;
+      *outAltered = true;
+    }
+  } else if (inPosition == nsIWindowMediator::zLevelBottom) {
+    if (mTopmostWindow && mTopmostWindow->mHigher->mZLevel < inZ) {
+      // asked for bottommost, can't have it. locate lowest allowed position.
+      do {
+        info = info->mHigher;
+        if (info->mZLevel >= inZ)
+          break;
+      } while (info != mTopmostWindow);
+
+      *outPosition = nsIWindowMediator::zLevelBelow;
+      belowWindow = info->mWindow;
+      *outAltered = true;
+    }
+  } else {
+    unsigned long relativeZ;
+
+    // check that we're in the right z-plane
+    if (found) {
+      belowWindow = info->mWindow;
+      relativeZ = info->mZLevel;
+      if (relativeZ > inZ) {
+        // might be OK. is lower window, if any, lower?
+        if (info->mLower != info && info->mLower->mZLevel > inZ) {
+          do {
+            if (info->mZLevel <= inZ)
+              break;
+            info = info->mLower;
+          } while (info != mTopmostWindow);
+
+          belowWindow = info->mHigher->mWindow;
+          *outAltered = true;
+        }
+      } else if (relativeZ < inZ) {
+        // nope. look for a higher window to be behind.
+        do {
+          info = info->mHigher;
+          if (info->mZLevel >= inZ)
+            break;
+        } while (info != mTopmostWindow);
+
+        if (info->mZLevel >= inZ)
+          belowWindow = info->mWindow;
+        else
+          *outPosition = nsIWindowMediator::zLevelTop;
+        *outAltered = true;
+      } // else they're equal, so it's OK
+    }
+  }
+
+  if (NS_SUCCEEDED(result) && belowWindow) {
+    nsCOMPtr<nsIBaseWindow> base(do_QueryInterface(belowWindow));
+    if (base)
+      base->GetMainWidget(outBelow);
+    else
+      result = NS_ERROR_NO_INTERFACE;
+  }
+
+  return result;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::SetZPosition(
+                nsIXULWindow *inWindow,
+                uint32_t      inPosition,
+                nsIXULWindow *inBelow)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  nsWindowInfo *inInfo,
+               *belowInfo;
+
+  if ((inPosition != nsIWindowMediator::zLevelTop &&
+       inPosition != nsIWindowMediator::zLevelBottom &&
+       inPosition != nsIWindowMediator::zLevelBelow) ||
+      !inWindow) {
+    return NS_ERROR_INVALID_ARG;
+  }
+
+  if (mSortingZOrder) // don't fight SortZOrder()
+    return NS_OK;
+
+  NS_ENSURE_STATE(mReady);
+
+  /* Locate inWindow and unlink it from the z-order list.
+     It's important we look for it in the age list, not the z-order list.
+     This is because the former is guaranteed complete, while
+     now may be this window's first exposure to the latter. */
+  inInfo = GetInfoFor(inWindow);
+  if (!inInfo)
+    return NS_ERROR_INVALID_ARG;
+
+  // locate inBelow, place inWindow behind it
+  if (inPosition == nsIWindowMediator::zLevelBelow) {
+    belowInfo = GetInfoFor(inBelow);
+    // it had better also be in the z-order list
+    if (belowInfo &&
+        belowInfo->mYounger != belowInfo && belowInfo->mLower == belowInfo) {
+      belowInfo = nullptr;
+    }
+    if (!belowInfo) {
+      if (inBelow)
+        return NS_ERROR_INVALID_ARG;
+      else
+        inPosition = nsIWindowMediator::zLevelTop;
+    }
+  }
+  if (inPosition == nsIWindowMediator::zLevelTop ||
+      inPosition == nsIWindowMediator::zLevelBottom)
+    belowInfo = mTopmostWindow ? mTopmostWindow->mHigher : nullptr;
+
+  if (inInfo != belowInfo) {
+    inInfo->Unlink(false, true);
+    inInfo->InsertAfter(nullptr, belowInfo);
+  }
+  if (inPosition == nsIWindowMediator::zLevelTop)
+    mTopmostWindow = inInfo;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::GetZLevel(nsIXULWindow *aWindow, uint32_t *_retval)
+{
+  NS_ENSURE_ARG_POINTER(_retval);
+  *_retval = nsIXULWindow::normalZ;
+  nsWindowInfo *info = GetInfoFor(aWindow);
+  if (info) {
+    *_retval = info->mZLevel;
+  } else {
+    NS_WARNING("getting z level of unregistered window");
+    // this goes off during window destruction
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::SetZLevel(nsIXULWindow *aWindow, uint32_t aZLevel)
+{
+  MOZ_RELEASE_ASSERT(NS_IsMainThread());
+  NS_ENSURE_STATE(mReady);
+
+  nsWindowInfo *info = GetInfoFor(aWindow);
+  NS_ASSERTION(info, "setting z level of unregistered window");
+  if (!info)
+    return NS_ERROR_FAILURE;
+
+  if (info->mZLevel != aZLevel) {
+    bool lowered = info->mZLevel > aZLevel;
+    info->mZLevel = aZLevel;
+    if (lowered)
+      SortZOrderFrontToBack();
+    else
+      SortZOrderBackToFront();
+  }
+  return NS_OK;
+}
+
+/*   Fix potentially out-of-order windows by performing an insertion sort
+   on the z-order list. The method will work no matter how broken the
+   list, but its assumed usage is immediately after one window's z level
+   has been changed, so one window is potentially out of place. Such a sort
+   is most efficiently done in a particular direction. Use this one
+   if a window's z level has just been reduced, so the sort is most efficiently
+   done front to back.
+     Note it's hardly worth going to all the trouble to write two versions
+   of this method except that if we choose the inefficient sorting direction,
+   on slow systems windows could visibly bubble around the window that
+   was moved.
+*/
+void
+nsWindowMediator::SortZOrderFrontToBack()
+{
+  nsWindowInfo *scan,   // scans list looking for problems
+               *search, // searches for correct placement for scan window
+               *prev,   // previous search element
+               *lowest; // bottom-most window in list
+  bool         finished;
+
+  if (!mTopmostWindow) // early during program execution there's no z list yet
+    return;            // there's also only one window, so this is not dangerous
+
+  mSortingZOrder = true;
+
+  /* Step through the list from top to bottom. If we find a window which
+     should be moved down in the list, move it to its highest legal position. */
+  do {
+    finished = true;
+    lowest = mTopmostWindow->mHigher;
+    scan = mTopmostWindow;
+    while (scan != lowest) {
+      uint32_t scanZ = scan->mZLevel;
+      if (scanZ < scan->mLower->mZLevel) { // out of order
+        search = scan->mLower;
+        do {
+          prev = search;
+          search = search->mLower;
+        } while (prev != lowest && scanZ < search->mZLevel);
+
+        // reposition |scan| within the list
+        if (scan == mTopmostWindow)
+          mTopmostWindow = scan->mLower;
+        scan->Unlink(false, true);
+        scan->InsertAfter(nullptr, prev);
+
+        // fix actual window order
+        nsCOMPtr<nsIBaseWindow> base;
+        nsCOMPtr<nsIWidget> scanWidget;
+        nsCOMPtr<nsIWidget> prevWidget;
+        base = do_QueryInterface(scan->mWindow);
+        if (base)
+          base->GetMainWidget(getter_AddRefs(scanWidget));
+        base = do_QueryInterface(prev->mWindow);
+        if (base)
+          base->GetMainWidget(getter_AddRefs(prevWidget));
+        if (scanWidget)
+          scanWidget->PlaceBehind(eZPlacementBelow, prevWidget, false);
+
+        finished = false;
+        break;
+      }
+      scan = scan->mLower;
+    }
+  } while (!finished);
+
+  mSortingZOrder = false;
+}
+
+// see comment for SortZOrderFrontToBack
+void
+nsWindowMediator::SortZOrderBackToFront()
+{
+  nsWindowInfo *scan,   // scans list looking for problems
+               *search, // searches for correct placement for scan window
+               *lowest; // bottom-most window in list
+  bool         finished;
+
+  if (!mTopmostWindow) // early during program execution there's no z list yet
+    return;            // there's also only one window, so this is not dangerous
+
+  mSortingZOrder = true;
+
+  /* Step through the list from bottom to top. If we find a window which
+     should be moved up in the list, move it to its lowest legal position. */
+  do {
+    finished = true;
+    lowest = mTopmostWindow->mHigher;
+    scan = lowest;
+    while (scan != mTopmostWindow) {
+      uint32_t scanZ = scan->mZLevel;
+      if (scanZ > scan->mHigher->mZLevel) { // out of order
+        search = scan;
+        do {
+          search = search->mHigher;
+        } while (search != lowest && scanZ > search->mZLevel);
+
+        // reposition |scan| within the list
+        if (scan != search && scan != search->mLower) {
+          scan->Unlink(false, true);
+          scan->InsertAfter(nullptr, search);
+        }
+        if (search == lowest)
+          mTopmostWindow = scan;
+
+        // fix actual window order
+        nsCOMPtr<nsIBaseWindow> base;
+        nsCOMPtr<nsIWidget> scanWidget;
+        nsCOMPtr<nsIWidget> searchWidget;
+        base = do_QueryInterface(scan->mWindow);
+        if (base)
+          base->GetMainWidget(getter_AddRefs(scanWidget));
+        if (mTopmostWindow != scan) {
+          base = do_QueryInterface(search->mWindow);
+          if (base)
+            base->GetMainWidget(getter_AddRefs(searchWidget));
+        }
+        if (scanWidget)
+          scanWidget->PlaceBehind(eZPlacementBelow, searchWidget, false);
+        finished = false;
+        break;
+      }
+      scan = scan->mHigher;
+    }
+  } while (!finished);
+
+  mSortingZOrder = false;
+}
+
+NS_IMPL_ISUPPORTS(nsWindowMediator,
+  nsIWindowMediator_44,
+  nsIWindowMediator,
+  nsIObserver,
+  nsISupportsWeakReference)
+
+NS_IMETHODIMP
+nsWindowMediator::AddListener(nsIWindowMediatorListener* aListener)
+{
+  NS_ENSURE_ARG_POINTER(aListener);
+  
+  mListeners.AppendObject(aListener);
+  
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::RemoveListener(nsIWindowMediatorListener* aListener)
+{
+  NS_ENSURE_ARG_POINTER(aListener);
+
+  mListeners.RemoveObject(aListener);
+  
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsWindowMediator::Observe(nsISupports* aSubject,
+                          const char* aTopic,
+                          const char16_t* aData)
+{
+  if (!strcmp(aTopic, "xpcom-shutdown") && mReady) {
+    MOZ_RELEASE_ASSERT(NS_IsMainThread());
+    while (mOldestWindow)
+      UnregisterWindow(mOldestWindow);
+    mReady = false;
+  }
+  return NS_OK;
+}
+
+bool
+notifyOpenWindow(nsIWindowMediatorListener *aListener, void* aData)
+{
+  WindowTitleData* winData = static_cast<WindowTitleData*>(aData);
+  aListener->OnOpenWindow(winData->mWindow);
+
+  return true;
+}
+
+bool
+notifyCloseWindow(nsIWindowMediatorListener *aListener, void* aData)
+{
+  WindowTitleData* winData = static_cast<WindowTitleData*>(aData);
+  aListener->OnCloseWindow(winData->mWindow);
+
+  return true;
+}
+
+bool 
+notifyWindowTitleChange(nsIWindowMediatorListener *aListener, void* aData)
+{
+  WindowTitleData* titleData = reinterpret_cast<WindowTitleData*>(aData);
+  aListener->OnWindowTitleChange(titleData->mWindow, titleData->mTitle);
+
+  return true;
+}
diff --git a/xpfe/appshell/nsWindowMediator.h b/xpfe/appshell/nsWindowMediator.h
new file mode 100644
index 000000000..a0eaab56d
--- /dev/null
+++ b/xpfe/appshell/nsWindowMediator.h
@@ -0,0 +1,78 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsWindowMediator_h_
+#define nsWindowMediator_h_
+
+#include "nsCOMPtr.h"
+#include "nsIWindowMediator.h"
+#include "nsIObserver.h"
+#include "nsTArray.h"
+#include "nsXPIDLString.h"
+#include "nsWeakReference.h"
+#include "nsCOMArray.h"
+
+class nsAppShellWindowEnumerator;
+class nsASXULWindowEarlyToLateEnumerator;
+class nsASDOMWindowEarlyToLateEnumerator;
+class nsASDOMWindowFrontToBackEnumerator;
+class nsASXULWindowFrontToBackEnumerator;
+class nsASDOMWindowBackToFrontEnumerator;
+class nsASXULWindowBackToFrontEnumerator;
+class nsIWindowMediatorListener;
+struct nsWindowInfo;
+
+class nsWindowMediator :
+  public nsIWindowMediator_44,
+  public nsIObserver,
+  public nsSupportsWeakReference
+{
+friend class nsAppShellWindowEnumerator;
+friend class nsASXULWindowEarlyToLateEnumerator;
+friend class nsASDOMWindowEarlyToLateEnumerator;
+friend class nsASDOMWindowFrontToBackEnumerator;
+friend class nsASXULWindowFrontToBackEnumerator;
+friend class nsASDOMWindowBackToFrontEnumerator;
+friend class nsASXULWindowBackToFrontEnumerator;
+
+protected:
+  virtual ~nsWindowMediator();
+
+public:
+  nsWindowMediator();
+
+  nsresult Init();
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIWINDOWMEDIATOR
+  NS_DECL_NSIWINDOWMEDIATOR_44
+  NS_DECL_NSIOBSERVER
+
+  static nsresult GetDOMWindow(nsIXULWindow* inWindow,
+                               nsCOMPtr<nsPIDOMWindowOuter>& outDOMWindow);
+
+private:
+  int32_t AddEnumerator(nsAppShellWindowEnumerator* inEnumerator);
+  int32_t RemoveEnumerator(nsAppShellWindowEnumerator* inEnumerator);
+  nsWindowInfo* MostRecentWindowInfo(const char16_t* inType,
+                                     bool aSkipPrivateBrowsingOrClosed = false);
+
+  nsresult      UnregisterWindow(nsWindowInfo *inInfo);
+  nsWindowInfo *GetInfoFor(nsIXULWindow *aWindow);
+  nsWindowInfo *GetInfoFor(nsIWidget *aWindow);
+  void          SortZOrderFrontToBack();
+  void          SortZOrderBackToFront();
+
+  nsTArray<nsAppShellWindowEnumerator*> mEnumeratorList;
+  nsWindowInfo *mOldestWindow;
+  nsWindowInfo *mTopmostWindow;
+  int32_t       mTimeStamp;
+  bool          mSortingZOrder;
+  bool          mReady;
+
+  nsCOMArray<nsIWindowMediatorListener> mListeners;
+};
+
+#endif
diff --git a/xpfe/appshell/nsXULWindow.cpp b/xpfe/appshell/nsXULWindow.cpp
new file mode 100644
index 000000000..8f2d9fde5
--- /dev/null
+++ b/xpfe/appshell/nsXULWindow.cpp
@@ -0,0 +1,2334 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 ci et: */
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "mozilla/MathAlgorithms.h"
+
+// Local includes
+#include "nsXULWindow.h"
+#include <algorithm>
+
+// Helper classes
+#include "nsPrintfCString.h"
+#include "nsString.h"
+#include "nsWidgetsCID.h"
+#include "nsThreadUtils.h"
+#include "nsNetCID.h"
+#include "nsQueryObject.h"
+#include "mozilla/Sprintf.h"
+
+//Interfaces needed to be included
+#include "nsIAppShell.h"
+#include "nsIAppShellService.h"
+#include "nsIServiceManager.h"
+#include "nsIContentViewer.h"
+#include "nsIDocument.h"
+#include "nsIDOMDocument.h"
+#include "nsIDOMXULDocument.h"
+#include "nsIDOMElement.h"
+#include "nsIDOMXULElement.h"
+#include "nsPIDOMWindow.h"
+#include "nsIDOMScreen.h"
+#include "nsIEmbeddingSiteWindow.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsIIOService.h"
+#include "nsILoadContext.h"
+#include "nsIObserverService.h"
+#include "nsIWindowMediator.h"
+#include "nsIScreenManager.h"
+#include "nsIScreen.h"
+#include "nsIScrollable.h"
+#include "nsIScriptSecurityManager.h"
+#include "nsIWindowWatcher.h"
+#include "nsIURI.h"
+#include "nsIDOMCSSStyleDeclaration.h"
+#include "nsAppShellCID.h"
+#include "nsReadableUtils.h"
+#include "nsStyleConsts.h"
+#include "nsPresContext.h"
+#include "nsContentUtils.h"
+#include "nsWebShellWindow.h" // get rid of this one, too...
+#include "nsGlobalWindow.h"
+
+#include "prenv.h"
+#include "mozilla/AutoRestore.h"
+#include "mozilla/Preferences.h"
+#include "mozilla/Services.h"
+#include "mozilla/dom/BarProps.h"
+#include "mozilla/dom/Element.h"
+#include "mozilla/dom/Event.h"
+#include "mozilla/dom/ScriptSettings.h"
+#include "mozilla/dom/TabParent.h"
+
+using namespace mozilla;
+using dom::AutoNoJSAPI;
+
+#define SIZEMODE_NORMAL     NS_LITERAL_STRING("normal")
+#define SIZEMODE_MAXIMIZED  NS_LITERAL_STRING("maximized")
+#define SIZEMODE_MINIMIZED  NS_LITERAL_STRING("minimized")
+#define SIZEMODE_FULLSCREEN NS_LITERAL_STRING("fullscreen")
+
+#define WINDOWTYPE_ATTRIBUTE NS_LITERAL_STRING("windowtype")
+
+#define PERSIST_ATTRIBUTE  NS_LITERAL_STRING("persist")
+#define SCREENX_ATTRIBUTE  NS_LITERAL_STRING("screenX")
+#define SCREENY_ATTRIBUTE  NS_LITERAL_STRING("screenY")
+#define WIDTH_ATTRIBUTE    NS_LITERAL_STRING("width")
+#define HEIGHT_ATTRIBUTE   NS_LITERAL_STRING("height")
+#define MODE_ATTRIBUTE     NS_LITERAL_STRING("sizemode")
+#define ZLEVEL_ATTRIBUTE   NS_LITERAL_STRING("zlevel")
+
+
+//*****************************************************************************
+//***    nsXULWindow: Object Management
+//*****************************************************************************
+
+nsXULWindow::nsXULWindow(uint32_t aChromeFlags)
+  : mChromeTreeOwner(nullptr), 
+    mContentTreeOwner(nullptr),
+    mPrimaryContentTreeOwner(nullptr),
+    mModalStatus(NS_OK),
+    mContinueModalLoop(false),
+    mDebuting(false),
+    mChromeLoaded(false), 
+    mShowAfterLoad(false),
+    mIntrinsicallySized(false),
+    mCenterAfterLoad(false),
+    mIsHiddenWindow(false),
+    mLockedUntilChromeLoad(false),
+    mIgnoreXULSize(false),
+    mIgnoreXULPosition(false),
+    mChromeFlagsFrozen(false),
+    mIgnoreXULSizeMode(false),
+    mDestroying(false),
+    mRegistered(false),
+    mContextFlags(0),
+    mPersistentAttributesDirty(0),
+    mPersistentAttributesMask(0),
+    mChromeFlags(aChromeFlags)
+{
+}
+
+nsXULWindow::~nsXULWindow()
+{
+  Destroy();
+}
+
+//*****************************************************************************
+// nsXULWindow::nsISupports
+//*****************************************************************************
+
+NS_IMPL_ADDREF(nsXULWindow)
+NS_IMPL_RELEASE(nsXULWindow)
+
+NS_INTERFACE_MAP_BEGIN(nsXULWindow)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIXULWindow)
+  NS_INTERFACE_MAP_ENTRY(nsIXULWindow)
+  NS_INTERFACE_MAP_ENTRY(nsIBaseWindow)
+  NS_INTERFACE_MAP_ENTRY(nsIInterfaceRequestor)
+  NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
+  if (aIID.Equals(NS_GET_IID(nsXULWindow)))
+    foundInterface = reinterpret_cast<nsISupports*>(this);
+  else
+NS_INTERFACE_MAP_END
+
+//*****************************************************************************
+// nsXULWindow::nsIIntefaceRequestor
+//*****************************************************************************   
+
+NS_IMETHODIMP nsXULWindow::GetInterface(const nsIID& aIID, void** aSink)
+{
+  nsresult rv;
+
+  NS_ENSURE_ARG_POINTER(aSink);
+
+  if (aIID.Equals(NS_GET_IID(nsIPrompt))) {
+    rv = EnsurePrompter();
+    if (NS_FAILED(rv)) return rv;
+    return mPrompter->QueryInterface(aIID, aSink);
+  }   
+  if (aIID.Equals(NS_GET_IID(nsIAuthPrompt))) {
+    rv = EnsureAuthPrompter();
+    if (NS_FAILED(rv)) return rv;
+    return mAuthPrompter->QueryInterface(aIID, aSink);
+  }
+  if (aIID.Equals(NS_GET_IID(mozIDOMWindowProxy))) {
+    return GetWindowDOMWindow(reinterpret_cast<mozIDOMWindowProxy**>(aSink));
+  }
+  if (aIID.Equals(NS_GET_IID(nsIDOMWindow))) {
+    nsCOMPtr<mozIDOMWindowProxy> window = nullptr;
+    rv = GetWindowDOMWindow(getter_AddRefs(window));
+    nsCOMPtr<nsIDOMWindow> domWindow = do_QueryInterface(window);
+    domWindow.forget(aSink);
+    return rv;
+  }
+  if (aIID.Equals(NS_GET_IID(nsIDOMWindowInternal))) {
+    nsCOMPtr<mozIDOMWindowProxy> window = nullptr;
+    rv = GetWindowDOMWindow(getter_AddRefs(window));
+    nsCOMPtr<nsIDOMWindowInternal> domWindowInternal = do_QueryInterface(window);
+    domWindowInternal.forget(aSink);
+    return rv;
+  }
+  if (aIID.Equals(NS_GET_IID(nsIWebBrowserChrome)) && 
+    NS_SUCCEEDED(EnsureContentTreeOwner()) &&
+    NS_SUCCEEDED(mContentTreeOwner->QueryInterface(aIID, aSink)))
+    return NS_OK;
+
+  if (aIID.Equals(NS_GET_IID(nsIEmbeddingSiteWindow)) && 
+    NS_SUCCEEDED(EnsureContentTreeOwner()) &&
+    NS_SUCCEEDED(mContentTreeOwner->QueryInterface(aIID, aSink)))
+    return NS_OK;
+
+  return QueryInterface(aIID, aSink);
+}
+
+//*****************************************************************************
+// nsXULWindow::nsIXULWindow
+//*****************************************************************************   
+
+NS_IMETHODIMP nsXULWindow::GetDocShell(nsIDocShell** aDocShell)
+{
+  NS_ENSURE_ARG_POINTER(aDocShell);
+
+  *aDocShell = mDocShell;
+  NS_IF_ADDREF(*aDocShell);
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetZLevel(uint32_t *outLevel)
+{
+  nsCOMPtr<nsIWindowMediator> mediator(do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+  if (mediator)
+    mediator->GetZLevel(this, outLevel);
+  else
+    *outLevel = normalZ;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetZLevel(uint32_t aLevel)
+{
+  nsCOMPtr<nsIWindowMediator> mediator(do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+  if (!mediator)
+    return NS_ERROR_FAILURE;
+
+  uint32_t zLevel;
+  mediator->GetZLevel(this, &zLevel);
+  if (zLevel == aLevel)
+    return NS_OK;
+
+  /* refuse to raise a maximized window above the normal browser level,
+     for fear it could hide newly opened browser windows */
+  if (aLevel > nsIXULWindow::normalZ && mWindow) {
+    nsSizeMode sizeMode = mWindow->SizeMode();
+    if (sizeMode == nsSizeMode_Maximized || sizeMode == nsSizeMode_Fullscreen) {
+      return NS_ERROR_FAILURE;
+    }
+  }
+
+  // do it
+  mediator->SetZLevel(this, aLevel);
+  PersistentAttributesDirty(PAD_MISC);
+  SavePersistentAttributes();
+
+  nsCOMPtr<nsIContentViewer> cv;
+  mDocShell->GetContentViewer(getter_AddRefs(cv));
+  if (cv) {
+    nsCOMPtr<nsIDocument> doc = cv->GetDocument();
+    if (doc) {
+      ErrorResult rv;
+      RefPtr<dom::Event> event =
+        doc->CreateEvent(NS_LITERAL_STRING("Events"),rv);
+      if (event) {
+        event->InitEvent(NS_LITERAL_STRING("windowZLevel"), true, false);
+
+        event->SetTrusted(true);
+
+        bool defaultActionEnabled;
+        doc->DispatchEvent(event, &defaultActionEnabled);
+      }
+    }
+  }
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetContextFlags(uint32_t *aContextFlags)
+{
+  NS_ENSURE_ARG_POINTER(aContextFlags);
+  *aContextFlags = mContextFlags;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetContextFlags(uint32_t aContextFlags)
+{
+  mContextFlags = aContextFlags;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetChromeFlags(uint32_t *aChromeFlags)
+{
+  NS_ENSURE_ARG_POINTER(aChromeFlags);
+  *aChromeFlags = mChromeFlags;
+  /* mChromeFlags is kept up to date, except for scrollbar visibility.
+     That can be changed directly by the content DOM window, which
+     doesn't know to update the chrome window. So that we must check
+     separately. */
+
+  // however, it's pointless to ask if the window isn't set up yet
+  if (!mChromeLoaded)
+    return NS_OK;
+
+  if (GetContentScrollbarVisibility())
+    *aChromeFlags |= nsIWebBrowserChrome::CHROME_SCROLLBARS;
+  else
+    *aChromeFlags &= ~nsIWebBrowserChrome::CHROME_SCROLLBARS;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetChromeFlags(uint32_t aChromeFlags)
+{
+  NS_ASSERTION(!mChromeFlagsFrozen,
+               "SetChromeFlags() after AssumeChromeFlagsAreFrozen()!");
+
+  mChromeFlags = aChromeFlags;
+  if (mChromeLoaded)
+    NS_ENSURE_SUCCESS(ApplyChromeFlags(), NS_ERROR_FAILURE);
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::AssumeChromeFlagsAreFrozen()
+{
+  mChromeFlagsFrozen = true;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetIntrinsicallySized(bool aIntrinsicallySized)
+{
+  mIntrinsicallySized = aIntrinsicallySized;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetIntrinsicallySized(bool* aIntrinsicallySized)
+{
+  NS_ENSURE_ARG_POINTER(aIntrinsicallySized);
+
+  *aIntrinsicallySized = mIntrinsicallySized;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetPrimaryContentShell(nsIDocShellTreeItem** 
+   aDocShellTreeItem)
+{
+  NS_ENSURE_ARG_POINTER(aDocShellTreeItem);
+  NS_IF_ADDREF(*aDocShellTreeItem = mPrimaryContentShell);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsXULWindow::TabParentAdded(nsITabParent* aTab, bool aPrimary)
+{
+  if (aPrimary) {
+    mPrimaryTabParent = aTab;
+    mPrimaryContentShell = nullptr;
+  } else if (mPrimaryTabParent == aTab) {
+    mPrimaryTabParent = nullptr;
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsXULWindow::TabParentRemoved(nsITabParent* aTab)
+{
+  if (aTab == mPrimaryTabParent) {
+    mPrimaryTabParent = nullptr;
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsXULWindow::GetPrimaryTabParent(nsITabParent** aTab)
+{
+  nsCOMPtr<nsITabParent> tab = mPrimaryTabParent;
+  tab.forget(aTab);
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetContentShellById(const char16_t* aID, 
+   nsIDocShellTreeItem** aDocShellTreeItem)
+{
+  NS_ENSURE_ARG_POINTER(aDocShellTreeItem);
+  *aDocShellTreeItem = nullptr;
+
+  uint32_t count = mContentShells.Length();
+  for (uint32_t i = 0; i < count; i++) {
+    nsContentShellInfo* shellInfo = mContentShells.ElementAt(i);
+    if (shellInfo->id.Equals(aID)) {
+      *aDocShellTreeItem = nullptr;
+      if (shellInfo->child)
+        CallQueryReferent(shellInfo->child.get(), aDocShellTreeItem);
+      return NS_OK;
+    }
+  }
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP nsXULWindow::AddChildWindow(nsIXULWindow *aChild)
+{
+  // we're not really keeping track of this right now
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::RemoveChildWindow(nsIXULWindow *aChild)
+{
+  // we're not really keeping track of this right now
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::ShowModal()
+{
+  PROFILER_LABEL_FUNC(js::ProfileEntry::Category::OTHER);
+
+  // Store locally so it doesn't die on us
+  nsCOMPtr<nsIWidget> window = mWindow;
+  nsCOMPtr<nsIXULWindow> tempRef = this;  
+
+  window->SetModal(true);
+  mContinueModalLoop = true;
+  EnableParent(false);
+
+  {
+    AutoNoJSAPI nojsapi;
+    nsIThread *thread = NS_GetCurrentThread();
+    while (mContinueModalLoop) {
+      if (!NS_ProcessNextEvent(thread))
+        break;
+    }
+  }
+
+  mContinueModalLoop = false;
+  window->SetModal(false);
+  /*   Note there's no EnableParent(true) here to match the false one
+     above. That's done in ExitModalLoop. It's important that the parent
+     be re-enabled before this window is made invisible; to do otherwise
+     causes bizarre z-ordering problems. At this point, the window is
+     already invisible.
+       No known current implementation of Enable would have a problem with
+     re-enabling the parent twice, so we could do it again here without
+     breaking any current implementation. But that's unnecessary if the
+     modal loop is always exited using ExitModalLoop (the other way would be
+     to change the protected member variable directly.)
+  */
+
+  return mModalStatus;
+}
+
+//*****************************************************************************
+// nsXULWindow::nsIBaseWindow
+//*****************************************************************************   
+
+NS_IMETHODIMP nsXULWindow::InitWindow(nativeWindow aParentNativeWindow,
+   nsIWidget* parentWidget, int32_t x, int32_t y, int32_t cx, int32_t cy)   
+{
+  //XXX First Check In
+  NS_ASSERTION(false, "Not Yet Implemented");
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::Create()
+{
+  //XXX First Check In
+  NS_ASSERTION(false, "Not Yet Implemented");
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::Destroy()
+{
+  if (!mWindow)
+     return NS_OK;
+
+  // Ensure we don't reenter this code
+  if (mDestroying)
+    return NS_OK;
+
+  mozilla::AutoRestore<bool> guard(mDestroying);
+  mDestroying = true;
+
+  nsCOMPtr<nsIAppShellService> appShell(do_GetService(NS_APPSHELLSERVICE_CONTRACTID));
+  NS_ASSERTION(appShell, "Couldn't get appShell... xpcom shutdown?");
+  if (appShell)
+    appShell->UnregisterTopLevelWindow(static_cast<nsIXULWindow*>(this));
+
+  nsCOMPtr<nsIXULWindow> parentWindow(do_QueryReferent(mParentWindow));
+  if (parentWindow)
+    parentWindow->RemoveChildWindow(this);
+
+  // let's make sure the window doesn't get deleted out from under us
+  // while we are trying to close....this can happen if the docshell
+  // we close ends up being the last owning reference to this xulwindow
+
+  // XXXTAB This shouldn't be an issue anymore because the ownership model
+  // only goes in one direction.  When webshell container is fully removed
+  // try removing this...
+
+  nsCOMPtr<nsIXULWindow> placeHolder = this;
+
+  // Remove modality (if any) and hide while destroying. More than
+  // a convenience, the hide prevents user interaction with the partially
+  // destroyed window. This is especially necessary when the eldest window
+  // in a stack of modal windows is destroyed first. It happens.
+  ExitModalLoop(NS_OK);
+  // XXX: Skip unmapping the window on Linux due to GLX hangs on the compositor
+  // thread with NVIDIA driver 310.32. We don't need to worry about user
+  // interactions with destroyed windows on X11 either.
+#ifndef MOZ_WIDGET_GTK
+  if (mWindow)
+    mWindow->Show(false);
+#endif
+
+#if defined(XP_WIN)
+  // We need to explicitly set the focus on Windows, but 
+  // only if the parent is visible.
+  nsCOMPtr<nsIBaseWindow> parent(do_QueryReferent(mParentWindow));
+  if (parent) {
+    nsCOMPtr<nsIWidget> parentWidget;
+    parent->GetMainWidget(getter_AddRefs(parentWidget));
+    if (!parentWidget || parentWidget->IsVisible()) {
+      nsCOMPtr<nsIBaseWindow> baseHiddenWindow;
+      if (appShell) {
+        nsCOMPtr<nsIXULWindow> hiddenWindow;
+        appShell->GetHiddenWindow(getter_AddRefs(hiddenWindow));
+        if (hiddenWindow)
+          baseHiddenWindow = do_GetInterface(hiddenWindow);
+      }
+      // somebody screwed up somewhere. hiddenwindow shouldn't be anybody's
+      // parent. still, when it happens, skip activating it.
+      if (baseHiddenWindow != parent) {
+        nsCOMPtr<nsIWidget> parentWidget;
+        parent->GetMainWidget(getter_AddRefs(parentWidget));
+        if (parentWidget)
+          parentWidget->PlaceBehind(eZPlacementTop, 0, true);
+      }
+    }
+  }
+#endif
+   
+  mDOMWindow = nullptr;
+  if (mDocShell) {
+    nsCOMPtr<nsIBaseWindow> shellAsWin(do_QueryInterface(mDocShell));
+    shellAsWin->Destroy();
+    mDocShell = nullptr; // this can cause reentrancy of this function
+  }
+
+  // Remove our ref on the content shells
+  uint32_t count = mContentShells.Length();
+  for (uint32_t i = 0; i < count; i++) {
+    nsContentShellInfo* shellInfo = mContentShells.ElementAt(i);
+    delete shellInfo;
+  }
+  mContentShells.Clear();
+  mPrimaryContentShell = nullptr;
+
+  if (mContentTreeOwner) {
+    mContentTreeOwner->XULWindow(nullptr);
+    NS_RELEASE(mContentTreeOwner);
+  }
+  if (mPrimaryContentTreeOwner) {
+    mPrimaryContentTreeOwner->XULWindow(nullptr);
+    NS_RELEASE(mPrimaryContentTreeOwner);
+  }
+  if (mChromeTreeOwner) {
+    mChromeTreeOwner->XULWindow(nullptr);
+    NS_RELEASE(mChromeTreeOwner);
+  }
+  if (mWindow) {
+    mWindow->SetWidgetListener(nullptr); // nsWebShellWindow hackery
+    mWindow->Destroy();
+    mWindow = nullptr;
+  }
+
+  if (!mIsHiddenWindow && mRegistered) {
+    /* Inform appstartup we've destroyed this window and it could
+       quit now if it wanted. This must happen at least after mDocShell
+       is destroyed, because onunload handlers fire then, and those being
+       script, anything could happen. A new window could open, even.
+       See bug 130719. */
+    nsCOMPtr<nsIObserverService> obssvc = services::GetObserverService();
+    NS_ASSERTION(obssvc, "Couldn't get observer service?");
+
+    if (obssvc)
+      obssvc->NotifyObservers(nullptr, "xul-window-destroyed", nullptr);
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetDevicePixelsPerDesktopPixel(double *aScale)
+{
+  *aScale = mWindow ? mWindow->GetDesktopToDeviceScale().scale : 1.0;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetUnscaledDevicePixelsPerCSSPixel(double *aScale)
+{
+  *aScale = mWindow ? mWindow->GetDefaultScale().scale : 1.0;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetPositionDesktopPix(int32_t aX, int32_t aY)
+{
+  nsresult rv = mWindow->Move(aX, aY);
+  NS_ENSURE_SUCCESS(rv, NS_ERROR_FAILURE);
+  if (!mChromeLoaded) {
+    // If we're called before the chrome is loaded someone obviously wants this
+    // window at this position. We don't persist this one-time position.
+    mIgnoreXULPosition = true;
+    return NS_OK;
+  }
+  PersistentAttributesDirty(PAD_POSITION);
+  SavePersistentAttributes();
+  return NS_OK;
+}
+
+// The parameters here are device pixels; do the best we can to convert to
+// desktop px, using the window's current scale factor (if available).
+NS_IMETHODIMP nsXULWindow::SetPosition(int32_t aX, int32_t aY)
+{
+  // Don't reset the window's size mode here - platforms that don't want to move
+  // maximized windows should reset it in their respective Move implementation.
+  DesktopToLayoutDeviceScale currScale = mWindow->GetDesktopToDeviceScale();
+  DesktopPoint pos = LayoutDeviceIntPoint(aX, aY) / currScale;
+  return SetPositionDesktopPix(pos.x, pos.y);
+}
+
+NS_IMETHODIMP nsXULWindow::GetPosition(int32_t* aX, int32_t* aY)
+{
+  return GetPositionAndSize(aX, aY, nullptr, nullptr);
+}
+
+NS_IMETHODIMP nsXULWindow::SetSize(int32_t aCX, int32_t aCY, bool aRepaint)
+{
+  /* any attempt to set the window's size or position overrides the window's
+     zoom state. this is important when these two states are competing while
+     the window is being opened. but it should probably just always be so. */
+  mWindow->SetSizeMode(nsSizeMode_Normal);
+
+  mIntrinsicallySized = false;
+
+  DesktopToLayoutDeviceScale scale = mWindow->GetDesktopToDeviceScale();
+  DesktopSize size = LayoutDeviceIntSize(aCX, aCY) / scale;
+  nsresult rv = mWindow->Resize(size.width, size.height, aRepaint);
+  NS_ENSURE_SUCCESS(rv, NS_ERROR_FAILURE);
+  if (!mChromeLoaded) {
+    // If we're called before the chrome is loaded someone obviously wants this
+    // window at this size & in the normal size mode (since it is the only mode
+    // in which setting dimensions makes sense). We don't persist this one-time
+    // size.
+    mIgnoreXULSize = true;
+    mIgnoreXULSizeMode = true;
+    return NS_OK;
+  }
+  PersistentAttributesDirty(PAD_SIZE);
+  SavePersistentAttributes();
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetSize(int32_t* aCX, int32_t* aCY)
+{
+  return GetPositionAndSize(nullptr, nullptr, aCX, aCY);
+}
+
+NS_IMETHODIMP nsXULWindow::SetPositionAndSize(int32_t aX, int32_t aY, 
+   int32_t aCX, int32_t aCY, uint32_t aFlags)
+{
+  /* any attempt to set the window's size or position overrides the window's
+     zoom state. this is important when these two states are competing while
+     the window is being opened. but it should probably just always be so. */
+  mWindow->SetSizeMode(nsSizeMode_Normal);
+
+  mIntrinsicallySized = false;
+
+  DesktopToLayoutDeviceScale scale = mWindow->GetDesktopToDeviceScale();
+  DesktopRect rect = LayoutDeviceIntRect(aX, aY, aCX, aCY) / scale;
+  nsresult rv = mWindow->Resize(rect.x, rect.y, rect.width, rect.height,
+                                !!(aFlags & nsIBaseWindow::eRepaint));
+  NS_ENSURE_SUCCESS(rv, NS_ERROR_FAILURE);
+  if (!mChromeLoaded) {
+    // If we're called before the chrome is loaded someone obviously wants this
+    // window at this size and position. We don't persist this one-time setting.
+    mIgnoreXULPosition = true;
+    mIgnoreXULSize = true;
+    mIgnoreXULSizeMode = true;
+    return NS_OK;
+  }
+  PersistentAttributesDirty(PAD_POSITION | PAD_SIZE);
+  SavePersistentAttributes();
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetPositionAndSize(int32_t* x, int32_t* y, int32_t* cx,
+   int32_t* cy)
+{
+
+  if (!mWindow)
+    return NS_ERROR_FAILURE;
+
+  LayoutDeviceIntRect rect = mWindow->GetScreenBounds();
+
+  if (x)
+    *x = rect.x;
+  if (y)
+    *y = rect.y;
+  if (cx)
+    *cx = rect.width;
+  if (cy)
+    *cy = rect.height;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::Center(nsIXULWindow *aRelative, bool aScreen, bool aAlert)
+{
+  int32_t  left, top, width, height,
+           ourWidth, ourHeight;
+  bool     screenCoordinates =  false,
+           windowCoordinates =  false;
+  nsresult result;
+
+  if (!mChromeLoaded) {
+    // note we lose the parameters. at time of writing, this isn't a problem.
+    mCenterAfterLoad = true;
+    return NS_OK;
+  }
+
+  if (!aScreen && !aRelative)
+    return NS_ERROR_INVALID_ARG;
+
+  nsCOMPtr<nsIScreenManager> screenmgr = do_GetService("@mozilla.org/gfx/screenmanager;1", &result);
+  if (NS_FAILED(result))
+    return result;
+
+  nsCOMPtr<nsIScreen> screen;
+
+  if (aRelative) {
+    nsCOMPtr<nsIBaseWindow> base(do_QueryInterface(aRelative, &result));
+    if (base) {
+      // get window rect
+      result = base->GetPositionAndSize(&left, &top, &width, &height);
+      if (NS_SUCCEEDED(result)) {
+        double scale;
+        if (NS_SUCCEEDED(base->GetDevicePixelsPerDesktopPixel(&scale))) {
+          left = NSToIntRound(left / scale);
+          top = NSToIntRound(top / scale);
+          width = NSToIntRound(width / scale);
+          height = NSToIntRound(height / scale);
+        }
+        // if centering on screen, convert that to the corresponding screen
+        if (aScreen)
+          screenmgr->ScreenForRect(left, top, width, height, getter_AddRefs(screen));
+        else
+          windowCoordinates = true;
+      } else {
+        // something's wrong with the reference window.
+        // fall back to the primary screen
+        aRelative = 0;
+        aScreen = true;
+      }
+    }
+  }
+  if (!aRelative) {
+    if (!mOpenerScreenRect.IsEmpty()) {
+      // FIXME - check if these are device or display pixels
+      screenmgr->ScreenForRect(mOpenerScreenRect.x, mOpenerScreenRect.y,
+                               mOpenerScreenRect.width, mOpenerScreenRect.height,
+                               getter_AddRefs(screen));
+    } else {
+      screenmgr->GetPrimaryScreen(getter_AddRefs(screen));
+    }
+  }
+
+  if (aScreen && screen) {
+    screen->GetAvailRectDisplayPix(&left, &top, &width, &height);
+    screenCoordinates = true;
+  }
+
+  if (screenCoordinates || windowCoordinates) {
+    NS_ASSERTION(mWindow, "what, no window?");
+    double scale = mWindow->GetDesktopToDeviceScale().scale;
+    GetSize(&ourWidth, &ourHeight);
+    int32_t scaledWidth, scaledHeight;
+    scaledWidth = NSToIntRound(ourWidth / scale);
+    scaledHeight = NSToIntRound(ourHeight / scale);
+    left += (width - scaledWidth) / 2;
+    top += (height - scaledHeight) / (aAlert ? 3 : 2);
+    if (windowCoordinates) {
+      mWindow->ConstrainPosition(false, &left, &top);
+    }
+    SetPosition(left * scale, top * scale);
+
+    // If moving the window caused it to change size,
+    // re-do the centering.
+    int32_t newWidth, newHeight;
+    GetSize(&newWidth, &newHeight);
+    if (newWidth != ourWidth || newHeight != ourHeight) {
+      return Center(aRelative, aScreen, aAlert);
+    }
+    return NS_OK;
+  }
+
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP nsXULWindow::Repaint(bool aForce)
+{
+  //XXX First Check In
+  NS_ASSERTION(false, "Not Yet Implemented");
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetParentWidget(nsIWidget** aParentWidget)
+{
+  NS_ENSURE_ARG_POINTER(aParentWidget);
+  NS_ENSURE_STATE(mWindow);
+
+  NS_IF_ADDREF(*aParentWidget = mWindow->GetParent());
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetParentWidget(nsIWidget* aParentWidget)
+{
+  //XXX First Check In
+  NS_ASSERTION(false, "Not Yet Implemented");
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetParentNativeWindow(nativeWindow* aParentNativeWindow)
+{
+  NS_ENSURE_ARG_POINTER(aParentNativeWindow);
+
+  nsCOMPtr<nsIWidget> parentWidget;
+  NS_ENSURE_SUCCESS(GetParentWidget(getter_AddRefs(parentWidget)), NS_ERROR_FAILURE);
+
+  if (parentWidget) {
+    *aParentNativeWindow = parentWidget->GetNativeData(NS_NATIVE_WIDGET);
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetParentNativeWindow(nativeWindow aParentNativeWindow)
+{
+  //XXX First Check In
+  NS_ASSERTION(false, "Not Yet Implemented");
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetNativeHandle(nsAString& aNativeHandle)
+{
+  nsCOMPtr<nsIWidget> mainWidget;
+  NS_ENSURE_SUCCESS(GetMainWidget(getter_AddRefs(mainWidget)), NS_ERROR_FAILURE);
+
+  if (mainWidget) {
+    nativeWindow nativeWindowPtr = mainWidget->GetNativeData(NS_NATIVE_WINDOW);
+    /* the nativeWindow pointer is converted to and exposed as a string. This
+       is a more reliable way not to lose information (as opposed to JS
+       |Number| for instance) */
+    aNativeHandle = NS_ConvertASCIItoUTF16(nsPrintfCString("0x%p", nativeWindowPtr));
+  }
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetVisibility(bool* aVisibility)
+{
+  NS_ENSURE_ARG_POINTER(aVisibility);
+
+  // Always claim to be visible for now. See bug
+  // https://bugzilla.mozilla.org/show_bug.cgi?id=306245.
+
+  *aVisibility = true;
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetVisibility(bool aVisibility)
+{
+  if (!mChromeLoaded) {
+    mShowAfterLoad = aVisibility;
+    return NS_OK;
+  }
+
+  if (mDebuting) {
+    return NS_OK;
+  }
+  mDebuting = true;  // (Show / Focus is recursive)
+
+  //XXXTAB Do we really need to show docshell and the window?  Isn't 
+  // the window good enough?
+  nsCOMPtr<nsIBaseWindow> shellAsWin(do_QueryInterface(mDocShell));
+  shellAsWin->SetVisibility(aVisibility);
+  // Store locally so it doesn't die on us. 'Show' can result in the window
+  // being closed with nsXULWindow::Destroy being called. That would set
+  // mWindow to null and posibly destroy the nsIWidget while its Show method
+  // is on the stack. We need to keep it alive until Show finishes.
+  nsCOMPtr<nsIWidget> window = mWindow;
+  window->Show(aVisibility);
+
+  nsCOMPtr<nsIWindowMediator> windowMediator(do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+  if (windowMediator)
+     windowMediator->UpdateWindowTimeStamp(static_cast<nsIXULWindow*>(this));
+
+  // notify observers so that we can hide the splash screen if possible
+  nsCOMPtr<nsIObserverService> obssvc = services::GetObserverService();
+  NS_ASSERTION(obssvc, "Couldn't get observer service.");
+  if (obssvc) {
+    obssvc->NotifyObservers(nullptr, "xul-window-visible", nullptr); 
+  }
+
+  mDebuting = false;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetEnabled(bool *aEnabled)
+{
+  NS_ENSURE_ARG_POINTER(aEnabled);
+
+  if (mWindow) {
+    *aEnabled = mWindow->IsEnabled();
+    return NS_OK;
+  }
+
+  *aEnabled = true; // better guess than most
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP nsXULWindow::SetEnabled(bool aEnable)
+{
+  if (mWindow) {
+    mWindow->Enable(aEnable);
+    return NS_OK;
+  }
+  return NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP nsXULWindow::GetMainWidget(nsIWidget** aMainWidget)
+{
+  NS_ENSURE_ARG_POINTER(aMainWidget);
+   
+  *aMainWidget = mWindow;
+  NS_IF_ADDREF(*aMainWidget);
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetFocus()
+{
+  //XXX First Check In
+  NS_ASSERTION(false, "Not Yet Implemented");
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetTitle(char16_t** aTitle)
+{
+  NS_ENSURE_ARG_POINTER(aTitle);
+
+  *aTitle = ToNewUnicode(mTitle);
+  if (!*aTitle)
+    return NS_ERROR_OUT_OF_MEMORY;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetTitle(const char16_t* aTitle)
+{
+  NS_ENSURE_STATE(mWindow);
+  mTitle.Assign(aTitle);
+  mTitle.StripChars("\n\r");
+  NS_ENSURE_SUCCESS(mWindow->SetTitle(mTitle), NS_ERROR_FAILURE);
+
+  // Tell the window mediator that a title has changed
+  nsCOMPtr<nsIWindowMediator> windowMediator(do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+  if (!windowMediator)
+    return NS_OK;
+
+  windowMediator->UpdateWindowTitle(static_cast<nsIXULWindow*>(this), aTitle);
+
+  return NS_OK;
+}
+
+
+//*****************************************************************************
+// nsXULWindow: Helpers
+//*****************************************************************************   
+
+NS_IMETHODIMP nsXULWindow::EnsureChromeTreeOwner()
+{
+  if (mChromeTreeOwner)
+    return NS_OK;
+
+  mChromeTreeOwner = new nsChromeTreeOwner();
+  NS_ADDREF(mChromeTreeOwner);
+  mChromeTreeOwner->XULWindow(this);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::EnsureContentTreeOwner()
+{
+  if (mContentTreeOwner)
+    return NS_OK;
+
+  mContentTreeOwner = new nsContentTreeOwner(false);
+  NS_ADDREF(mContentTreeOwner);
+  mContentTreeOwner->XULWindow(this);
+   
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::EnsurePrimaryContentTreeOwner()
+{
+  if (mPrimaryContentTreeOwner)
+    return NS_OK;
+
+  mPrimaryContentTreeOwner = new nsContentTreeOwner(true);
+  NS_ADDREF(mPrimaryContentTreeOwner);
+  mPrimaryContentTreeOwner->XULWindow(this);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::EnsurePrompter()
+{
+  if (mPrompter)
+    return NS_OK;
+   
+  nsCOMPtr<mozIDOMWindowProxy> ourWindow;
+  nsresult rv = GetWindowDOMWindow(getter_AddRefs(ourWindow));
+  if (NS_SUCCEEDED(rv)) {
+    nsCOMPtr<nsIWindowWatcher> wwatch = 
+        do_GetService(NS_WINDOWWATCHER_CONTRACTID);
+    if (wwatch)
+      wwatch->GetNewPrompter(ourWindow, getter_AddRefs(mPrompter));
+  }
+  return mPrompter ? NS_OK : NS_ERROR_FAILURE;
+}
+
+NS_IMETHODIMP nsXULWindow::EnsureAuthPrompter()
+{
+  if (mAuthPrompter)
+    return NS_OK;
+      
+  nsCOMPtr<mozIDOMWindowProxy> ourWindow;
+  nsresult rv = GetWindowDOMWindow(getter_AddRefs(ourWindow));
+  if (NS_SUCCEEDED(rv)) {
+    nsCOMPtr<nsIWindowWatcher> wwatch(do_GetService(NS_WINDOWWATCHER_CONTRACTID));
+    if (wwatch)
+      wwatch->GetNewAuthPrompter(ourWindow, getter_AddRefs(mAuthPrompter));
+  }
+  return mAuthPrompter ? NS_OK : NS_ERROR_FAILURE;
+}
+ 
+void nsXULWindow::OnChromeLoaded()
+{
+  nsresult rv = EnsureContentTreeOwner();
+
+  if (NS_SUCCEEDED(rv)) {
+    mChromeLoaded = true;
+    ApplyChromeFlags();
+    SyncAttributesToWidget();
+
+    int32_t specWidth = -1, specHeight = -1;
+    bool gotSize = false;
+
+    if (!mIgnoreXULSize) {
+      gotSize = LoadSizeFromXUL(specWidth, specHeight);
+    }
+
+    bool positionSet = !mIgnoreXULPosition;
+    nsCOMPtr<nsIXULWindow> parentWindow(do_QueryReferent(mParentWindow));
+#if defined(XP_UNIX) && !defined(XP_MACOSX)
+    // don't override WM placement on unix for independent, top-level windows
+    // (however, we think the benefits of intelligent dependent window placement
+    // trump that override.)
+    if (!parentWindow)
+      positionSet = false;
+#endif
+    if (positionSet) {
+      // We have to do this before sizing the window, because sizing depends
+      // on the resolution of the screen we're on. But positioning needs to
+      // know the size so that it can constrain to screen bounds.... as an
+      // initial guess here, we'll use the specified size (if any).
+      positionSet = LoadPositionFromXUL(specWidth, specHeight);
+    }
+
+    if (gotSize) {
+      SetSpecifiedSize(specWidth, specHeight);
+    }
+
+    if (mIntrinsicallySized) {
+      // (if LoadSizeFromXUL set the size, mIntrinsicallySized will be false)
+      nsCOMPtr<nsIContentViewer> cv;
+      mDocShell->GetContentViewer(getter_AddRefs(cv));
+      if (cv) {
+        nsCOMPtr<nsIDocShellTreeItem> docShellAsItem = do_QueryInterface(mDocShell);
+        nsCOMPtr<nsIDocShellTreeOwner> treeOwner;
+        docShellAsItem->GetTreeOwner(getter_AddRefs(treeOwner));
+        if (treeOwner) {
+          // GetContentSize can fail, so initialise |width| and |height| to be
+          // on the safe side.
+          int32_t width = 0, height = 0;
+          if (NS_SUCCEEDED(cv->GetContentSize(&width, &height))) {
+            treeOwner->SizeShellTo(docShellAsItem, width, height);
+            // Update specified size for the final LoadPositionFromXUL call.
+            specWidth = width;
+            specHeight = height;
+          }
+        }
+      }
+    }
+
+    // Now that we have set the window's final size, we can re-do its
+    // positioning so that it is properly constrained to the screen.
+    if (positionSet) {
+      LoadPositionFromXUL(specWidth, specHeight);
+    }
+
+    LoadMiscPersistentAttributesFromXUL();
+
+    if (mCenterAfterLoad && !positionSet) {
+      Center(parentWindow, parentWindow ? false : true, false);
+    }
+
+    if (mShowAfterLoad) {
+      SetVisibility(true);
+      // At this point the window may have been closed during Show(), so
+      // nsXULWindow::Destroy may already have been called. Take care!
+    }
+  }
+  mPersistentAttributesMask |= PAD_POSITION | PAD_SIZE | PAD_MISC;
+}
+
+// If aSpecWidth and/or aSpecHeight are > 0, we will use these CSS px sizes
+// to fit to the screen when staggering windows; if they're negative,
+// we use the window's current size instead.
+bool nsXULWindow::LoadPositionFromXUL(int32_t aSpecWidth, int32_t aSpecHeight)
+{
+  bool     gotPosition = false;
+
+  // if we're the hidden window, don't try to validate our size/position. We're
+  // special.
+  if (mIsHiddenWindow)
+    return false;
+
+  nsCOMPtr<dom::Element> windowElement = GetWindowDOMElement();
+  NS_ENSURE_TRUE(windowElement, false);
+
+  int32_t currX = 0;
+  int32_t currY = 0;
+  int32_t currWidth = 0;
+  int32_t currHeight = 0;
+  nsresult errorCode;
+  int32_t temp;
+
+  GetPositionAndSize(&currX, &currY, &currWidth, &currHeight);
+
+  // Convert to global display pixels for consistent window management across
+  // screens with diverse resolutions
+  double devToDesktopScale = 1.0 / mWindow->GetDesktopToDeviceScale().scale;
+  currX = NSToIntRound(currX * devToDesktopScale);
+  currY = NSToIntRound(currY * devToDesktopScale);
+
+  // For size, use specified value if > 0, else current value
+  double devToCSSScale = 1.0 / mWindow->GetDefaultScale().scale;
+  int32_t cssWidth =
+    aSpecWidth > 0 ? aSpecWidth : NSToIntRound(currWidth * devToCSSScale);
+  int32_t cssHeight =
+    aSpecHeight > 0 ? aSpecHeight : NSToIntRound(currHeight * devToCSSScale);
+
+  // Obtain the position information from the <xul:window> element.
+  int32_t specX = currX;
+  int32_t specY = currY;
+  nsAutoString posString;
+
+  windowElement->GetAttribute(SCREENX_ATTRIBUTE, posString);
+  temp = posString.ToInteger(&errorCode);
+  if (NS_SUCCEEDED(errorCode)) {
+    specX = temp;
+    gotPosition = true;
+  }
+  windowElement->GetAttribute(SCREENY_ATTRIBUTE, posString);
+  temp = posString.ToInteger(&errorCode);
+  if (NS_SUCCEEDED(errorCode)) {
+    specY = temp;
+    gotPosition = true;
+  }
+
+  if (gotPosition) {
+    // our position will be relative to our parent, if any
+    nsCOMPtr<nsIBaseWindow> parent(do_QueryReferent(mParentWindow));
+    if (parent) {
+      int32_t parentX, parentY;
+      if (NS_SUCCEEDED(parent->GetPosition(&parentX, &parentY))) {
+        double scale;
+        if (NS_SUCCEEDED(parent->GetDevicePixelsPerDesktopPixel(&scale))) {
+          parentX = NSToIntRound(parentX / scale);
+          parentY = NSToIntRound(parentY / scale);
+        }
+        specX += parentX;
+        specY += parentY;
+      }
+    }
+    else {
+      StaggerPosition(specX, specY, cssWidth, cssHeight);
+    }
+  }
+  mWindow->ConstrainPosition(false, &specX, &specY);
+  if (specX != currX || specY != currY) {
+    SetPositionDesktopPix(specX, specY);
+  }
+
+  return gotPosition;
+}
+
+bool
+nsXULWindow::LoadSizeFromXUL(int32_t& aSpecWidth, int32_t& aSpecHeight)
+{
+  bool     gotSize = false;
+
+  // if we're the hidden window, don't try to validate our size/position. We're
+  // special.
+  if (mIsHiddenWindow) {
+    return false;
+  }
+
+  nsCOMPtr<dom::Element> windowElement = GetWindowDOMElement();
+  NS_ENSURE_TRUE(windowElement, false);
+
+  nsresult errorCode;
+  int32_t temp;
+
+  // Obtain the sizing information from the <xul:window> element.
+  aSpecWidth = 100;
+  aSpecHeight = 100;
+  nsAutoString sizeString;
+
+  windowElement->GetAttribute(WIDTH_ATTRIBUTE, sizeString);
+  temp = sizeString.ToInteger(&errorCode);
+  if (NS_SUCCEEDED(errorCode) && temp > 0) {
+    aSpecWidth = std::max(temp, 100);
+    gotSize = true;
+  }
+  windowElement->GetAttribute(HEIGHT_ATTRIBUTE, sizeString);
+  temp = sizeString.ToInteger(&errorCode);
+  if (NS_SUCCEEDED(errorCode) && temp > 0) {
+    aSpecHeight = std::max(temp, 100);
+    gotSize = true;
+  }
+
+  return gotSize;
+}
+
+void
+nsXULWindow::SetSpecifiedSize(int32_t aSpecWidth, int32_t aSpecHeight)
+{
+  // constrain to screen size
+  nsCOMPtr<mozIDOMWindowProxy> domWindow;
+  GetWindowDOMWindow(getter_AddRefs(domWindow));
+  if (domWindow) {
+    auto* window = nsPIDOMWindowOuter::From(domWindow);
+    nsCOMPtr<nsIDOMScreen> screen = window->GetScreen();
+    if (screen) {
+      int32_t screenWidth;
+      int32_t screenHeight;
+      screen->GetAvailWidth(&screenWidth); // CSS pixels
+      screen->GetAvailHeight(&screenHeight);
+      if (aSpecWidth > screenWidth) {
+        aSpecWidth = screenWidth;
+      }
+      if (aSpecHeight > screenHeight) {
+        aSpecHeight = screenHeight;
+      }
+    }
+  }
+
+  NS_ASSERTION(mWindow, "we expected to have a window already");
+
+  int32_t currWidth = 0;
+  int32_t currHeight = 0;
+  GetSize(&currWidth, &currHeight); // returns device pixels
+
+  // convert specified values to device pixels, and resize if needed
+  double cssToDevPx = mWindow ? mWindow->GetDefaultScale().scale : 1.0;
+  aSpecWidth = NSToIntRound(aSpecWidth * cssToDevPx);
+  aSpecHeight = NSToIntRound(aSpecHeight * cssToDevPx);
+  mIntrinsicallySized = false;
+  if (aSpecWidth != currWidth || aSpecHeight != currHeight) {
+    SetSize(aSpecWidth, aSpecHeight, false);
+  }
+}
+
+/* Miscellaneous persistent attributes are attributes named in the
+   |persist| attribute, other than size and position. Those are special
+   because it's important to load those before one of the misc
+   attributes (sizemode) and they require extra processing. */
+bool nsXULWindow::LoadMiscPersistentAttributesFromXUL()
+{
+  bool     gotState = false;
+
+  /* There are no misc attributes of interest to the hidden window.
+     It's especially important not to try to validate that window's
+     size or position, because some platforms (Mac OS X) need to
+     make it visible and offscreen. */
+  if (mIsHiddenWindow)
+    return false;
+
+  nsCOMPtr<dom::Element> windowElement = GetWindowDOMElement();
+  NS_ENSURE_TRUE(windowElement, false);
+
+  nsAutoString stateString;
+
+  // sizemode
+  windowElement->GetAttribute(MODE_ATTRIBUTE, stateString);
+  nsSizeMode sizeMode = nsSizeMode_Normal;
+  /* ignore request to minimize, to not confuse novices
+  if (stateString.Equals(SIZEMODE_MINIMIZED))
+    sizeMode = nsSizeMode_Minimized;
+  */
+  if (!mIgnoreXULSizeMode &&
+      (stateString.Equals(SIZEMODE_MAXIMIZED) || stateString.Equals(SIZEMODE_FULLSCREEN))) {
+    /* Honor request to maximize only if the window is sizable.
+       An unsizable, unmaximizable, yet maximized window confuses
+       Windows OS and is something of a travesty, anyway. */
+    if (mChromeFlags & nsIWebBrowserChrome::CHROME_WINDOW_RESIZE) {
+      mIntrinsicallySized = false;
+
+      if (stateString.Equals(SIZEMODE_MAXIMIZED))
+        sizeMode = nsSizeMode_Maximized;
+      else
+        sizeMode = nsSizeMode_Fullscreen;
+    }
+  }
+
+  // If we are told to ignore the size mode attribute update the
+  // document so the attribute and window are in sync.
+  if (mIgnoreXULSizeMode) {
+    nsAutoString sizeString;
+    if (sizeMode == nsSizeMode_Maximized)
+      sizeString.Assign(SIZEMODE_MAXIMIZED);
+    else if (sizeMode == nsSizeMode_Fullscreen)
+      sizeString.Assign(SIZEMODE_FULLSCREEN);
+    else if (sizeMode == nsSizeMode_Normal)
+      sizeString.Assign(SIZEMODE_NORMAL);
+    if (!sizeString.IsEmpty()) {
+      ErrorResult rv;
+      windowElement->SetAttribute(MODE_ATTRIBUTE, sizeString, rv);
+    }
+  }
+
+  if (sizeMode == nsSizeMode_Fullscreen) {
+    nsCOMPtr<mozIDOMWindowProxy> ourWindow;
+    GetWindowDOMWindow(getter_AddRefs(ourWindow));
+    auto* piWindow = nsPIDOMWindowOuter::From(ourWindow);
+    piWindow->SetFullScreen(true);
+  } else {
+    mWindow->SetSizeMode(sizeMode);
+  }
+  gotState = true;
+
+  // zlevel
+  windowElement->GetAttribute(ZLEVEL_ATTRIBUTE, stateString);
+  if (!stateString.IsEmpty()) {
+    nsresult errorCode;
+    int32_t zLevel = stateString.ToInteger(&errorCode);
+    if (NS_SUCCEEDED(errorCode) && zLevel >= lowestZ && zLevel <= highestZ)
+      SetZLevel(zLevel);
+  }
+
+  return gotState;
+}
+
+/* Stagger windows of the same type so they don't appear on top of each other.
+   This code does have a scary double loop -- it'll keep passing through
+   the entire list of open windows until it finds a non-collision. Doesn't
+   seem to be a problem, but it deserves watching.
+   The aRequested{X,Y} parameters here are in desktop pixels;
+   the aSpec{Width,Height} parameters are CSS pixel dimensions.
+*/
+void nsXULWindow::StaggerPosition(int32_t &aRequestedX, int32_t &aRequestedY,
+                                  int32_t aSpecWidth, int32_t aSpecHeight)
+{
+  // These "constants" will be converted from CSS to desktop pixels
+  // for the appropriate screen, assuming we find a screen to use...
+  // hence they're not actually declared const here.
+  int32_t kOffset = 22;
+  uint32_t kSlop  = 4;
+
+  bool     keepTrying;
+  int      bouncedX = 0, // bounced off vertical edge of screen
+           bouncedY = 0; // bounced off horizontal edge
+
+  // look for any other windows of this type
+  nsCOMPtr<nsIWindowMediator> wm(do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+  if (!wm)
+    return;
+
+  nsCOMPtr<dom::Element> windowElement = GetWindowDOMElement();
+  if (!windowElement)
+    return;
+
+  nsCOMPtr<nsIXULWindow> ourXULWindow(this);
+
+  nsAutoString windowType;
+  windowElement->GetAttribute(WINDOWTYPE_ATTRIBUTE, windowType);
+
+  int32_t screenTop = 0,    // it's pointless to initialize these ...
+          screenRight = 0,  // ... but to prevent oversalubrious and ...
+          screenBottom = 0, // ... underbright compilers from ...
+          screenLeft = 0;   // ... issuing warnings.
+  bool    gotScreen = false;
+
+  { // fetch screen coordinates
+    nsCOMPtr<nsIScreenManager> screenMgr(do_GetService(
+                                         "@mozilla.org/gfx/screenmanager;1"));
+    if (screenMgr) {
+      nsCOMPtr<nsIScreen> ourScreen;
+      // the coordinates here are already display pixels
+      screenMgr->ScreenForRect(aRequestedX, aRequestedY,
+                               aSpecWidth, aSpecHeight,
+                               getter_AddRefs(ourScreen));
+      if (ourScreen) {
+        int32_t screenWidth, screenHeight;
+        ourScreen->GetAvailRectDisplayPix(&screenLeft, &screenTop,
+                                          &screenWidth, &screenHeight);
+        screenBottom = screenTop + screenHeight;
+        screenRight = screenLeft + screenWidth;
+        // Get the screen's scaling factors and convert staggering constants
+        // from CSS px to desktop pixel units
+        double desktopToDeviceScale = 1.0, cssToDeviceScale = 1.0;
+        ourScreen->GetContentsScaleFactor(&desktopToDeviceScale);
+        ourScreen->GetDefaultCSSScaleFactor(&cssToDeviceScale);
+        double cssToDesktopFactor = cssToDeviceScale / desktopToDeviceScale;
+        kOffset = NSToIntRound(kOffset * cssToDesktopFactor);
+        kSlop = NSToIntRound(kSlop * cssToDesktopFactor);
+        // Convert dimensions from CSS to desktop pixels
+        aSpecWidth = NSToIntRound(aSpecWidth * cssToDesktopFactor);
+        aSpecHeight = NSToIntRound(aSpecHeight * cssToDesktopFactor);
+        gotScreen = true;
+      }
+    }
+  }
+
+  // One full pass through all windows of this type, repeat until no collisions.
+  do {
+    keepTrying = false;
+    nsCOMPtr<nsISimpleEnumerator> windowList;
+    wm->GetXULWindowEnumerator(windowType.get(), getter_AddRefs(windowList));
+
+    if (!windowList)
+      break;
+
+    // One full pass through all windows of this type, offset and stop on collision.
+    do {
+      bool more;
+      windowList->HasMoreElements(&more);
+      if (!more)
+        break;
+
+      nsCOMPtr<nsISupports> supportsWindow;
+      windowList->GetNext(getter_AddRefs(supportsWindow));
+
+      nsCOMPtr<nsIXULWindow> listXULWindow(do_QueryInterface(supportsWindow));
+      if (listXULWindow != ourXULWindow) {
+        int32_t listX, listY;
+        nsCOMPtr<nsIBaseWindow> listBaseWindow(do_QueryInterface(supportsWindow));
+        listBaseWindow->GetPosition(&listX, &listY);
+        double scale;
+        if (NS_SUCCEEDED(listBaseWindow->GetDevicePixelsPerDesktopPixel(&scale))) {
+          listX = NSToIntRound(listX / scale);
+          listY = NSToIntRound(listY / scale);
+        }
+
+        if (Abs(listX - aRequestedX) <= kSlop && Abs(listY - aRequestedY) <= kSlop) {
+          // collision! offset and start over
+          if (bouncedX & 0x1)
+            aRequestedX -= kOffset;
+          else
+            aRequestedX += kOffset;
+          aRequestedY += kOffset;
+
+          if (gotScreen) {
+            // if we're moving to the right and we need to bounce...
+            if (!(bouncedX & 0x1) && ((aRequestedX + aSpecWidth) > screenRight)) {
+              aRequestedX = screenRight - aSpecWidth;
+              ++bouncedX;
+            }
+
+            // if we're moving to the left and we need to bounce...
+            if ((bouncedX & 0x1) && aRequestedX < screenLeft) {
+              aRequestedX = screenLeft;
+              ++bouncedX;
+            }
+
+            // if we hit the bottom then bounce to the top
+            if (aRequestedY + aSpecHeight > screenBottom) {
+              aRequestedY = screenTop;
+              ++bouncedY;
+            }
+          }
+
+          /* loop around again,
+             but it's time to give up once we've covered the screen.
+             there's a potential infinite loop with lots of windows. */
+          keepTrying = bouncedX < 2 || bouncedY == 0;
+          break;
+        }
+      }
+    } while(1);
+  } while (keepTrying);
+}
+
+void nsXULWindow::SyncAttributesToWidget()
+{
+  nsCOMPtr<dom::Element> windowElement = GetWindowDOMElement();
+  if (!windowElement)
+    return;
+
+  nsAutoString attr;
+
+  // "hidechrome" attribute
+  if (windowElement->AttrValueIs(kNameSpaceID_None, nsGkAtoms::hidechrome,
+                                 nsGkAtoms::_true, eCaseMatters)) {
+    mWindow->HideWindowChrome(true);
+  }
+
+  // "chromemargin" attribute
+  nsIntMargin margins;
+  windowElement->GetAttribute(NS_LITERAL_STRING("chromemargin"), attr);
+  if (nsContentUtils::ParseIntMarginValue(attr, margins)) {
+    LayoutDeviceIntMargin tmp = LayoutDeviceIntMargin::FromUnknownMargin(margins);
+    mWindow->SetNonClientMargins(tmp);
+  }
+
+  // "windowtype" attribute
+  windowElement->GetAttribute(WINDOWTYPE_ATTRIBUTE, attr);
+  if (!attr.IsEmpty()) {
+    mWindow->SetWindowClass(attr);
+  }
+
+  // "id" attribute for icon
+  windowElement->GetAttribute(NS_LITERAL_STRING("id"), attr);
+  if (attr.IsEmpty()) {
+    attr.AssignLiteral("default");
+  }
+  mWindow->SetIcon(attr);
+
+  // "drawtitle" attribute
+  windowElement->GetAttribute(NS_LITERAL_STRING("drawtitle"), attr);
+  mWindow->SetDrawsTitle(attr.LowerCaseEqualsLiteral("true"));
+
+  // "toggletoolbar" attribute
+  windowElement->GetAttribute(NS_LITERAL_STRING("toggletoolbar"), attr);
+  mWindow->SetShowsToolbarButton(attr.LowerCaseEqualsLiteral("true"));
+
+  // "fullscreenbutton" attribute
+  windowElement->GetAttribute(NS_LITERAL_STRING("fullscreenbutton"), attr);
+  mWindow->SetShowsFullScreenButton(attr.LowerCaseEqualsLiteral("true"));
+
+  // "macanimationtype" attribute
+  windowElement->GetAttribute(NS_LITERAL_STRING("macanimationtype"), attr);
+  if (attr.EqualsLiteral("document")) {
+    mWindow->SetWindowAnimationType(nsIWidget::eDocumentWindowAnimation);
+  }
+}
+
+NS_IMETHODIMP nsXULWindow::SavePersistentAttributes()
+{
+  // can happen when the persistence timer fires at an inopportune time
+  // during window shutdown
+  if (!mDocShell)
+    return NS_ERROR_FAILURE;
+
+  nsCOMPtr<dom::Element> docShellElement = GetWindowDOMElement();
+  if (!docShellElement)
+    return NS_ERROR_FAILURE;
+
+  nsAutoString   persistString;
+  docShellElement->GetAttribute(PERSIST_ATTRIBUTE, persistString);
+  if (persistString.IsEmpty()) { // quick check which sometimes helps
+    mPersistentAttributesDirty = 0;
+    return NS_OK;
+  }
+
+  bool isFullscreen = false;
+  if (nsPIDOMWindowOuter* domWindow = mDocShell->GetWindow()) {
+    isFullscreen = domWindow->GetFullScreen();
+  }
+
+  // get our size, position and mode to persist
+  LayoutDeviceIntRect rect;
+  bool gotRestoredBounds = NS_SUCCEEDED(mWindow->GetRestoredBounds(rect));
+
+  // we use CSS pixels for size, but desktop pixels for position
+  CSSToLayoutDeviceScale sizeScale = mWindow->GetDefaultScale();
+  DesktopToLayoutDeviceScale posScale = mWindow->GetDesktopToDeviceScale();
+
+  // make our position relative to our parent, if any
+  nsCOMPtr<nsIBaseWindow> parent(do_QueryReferent(mParentWindow));
+  if (parent && gotRestoredBounds) {
+    int32_t parentX, parentY;
+    if (NS_SUCCEEDED(parent->GetPosition(&parentX, &parentY))) {
+      rect.x -= parentX;
+      rect.y -= parentY;
+    }
+  }
+
+  char                        sizeBuf[10];
+  nsAutoString                sizeString;
+  nsAutoString                windowElementId;
+  nsCOMPtr<nsIDOMXULDocument> ownerXULDoc;
+
+  // fetch docShellElement's ID and XUL owner document
+  ownerXULDoc = do_QueryInterface(docShellElement->OwnerDoc());
+  if (docShellElement->IsXULElement()) {
+    docShellElement->GetId(windowElementId);
+  }
+
+  bool shouldPersist = !isFullscreen && ownerXULDoc;
+  ErrorResult rv;
+  // (only for size elements which are persisted)
+  if ((mPersistentAttributesDirty & PAD_POSITION) && gotRestoredBounds) {
+    if (persistString.Find("screenX") >= 0) {
+      SprintfLiteral(sizeBuf, "%d", NSToIntRound(rect.x / posScale.scale));
+      sizeString.AssignWithConversion(sizeBuf);
+      docShellElement->SetAttribute(SCREENX_ATTRIBUTE, sizeString, rv);
+      if (shouldPersist) {
+        ownerXULDoc->Persist(windowElementId, SCREENX_ATTRIBUTE);
+      }
+    }
+    if (persistString.Find("screenY") >= 0) {
+      SprintfLiteral(sizeBuf, "%d", NSToIntRound(rect.y / posScale.scale));
+      sizeString.AssignWithConversion(sizeBuf);
+      docShellElement->SetAttribute(SCREENY_ATTRIBUTE, sizeString, rv);
+      if (shouldPersist) {
+        ownerXULDoc->Persist(windowElementId, SCREENY_ATTRIBUTE);
+      }
+    }
+  }
+
+  if ((mPersistentAttributesDirty & PAD_SIZE) && gotRestoredBounds) {
+    if (persistString.Find("width") >= 0) {
+      SprintfLiteral(sizeBuf, "%d", NSToIntRound(rect.width / sizeScale.scale));
+      sizeString.AssignWithConversion(sizeBuf);
+      docShellElement->SetAttribute(WIDTH_ATTRIBUTE, sizeString, rv);
+      if (shouldPersist) {
+        ownerXULDoc->Persist(windowElementId, WIDTH_ATTRIBUTE);
+      }
+    }
+    if (persistString.Find("height") >= 0) {
+      SprintfLiteral(sizeBuf, "%d", NSToIntRound(rect.height / sizeScale.scale));
+      sizeString.AssignWithConversion(sizeBuf);
+      docShellElement->SetAttribute(HEIGHT_ATTRIBUTE, sizeString, rv);
+      if (shouldPersist) {
+        ownerXULDoc->Persist(windowElementId, HEIGHT_ATTRIBUTE);
+      }
+    }
+  }
+
+  if (mPersistentAttributesDirty & PAD_MISC) {
+    nsSizeMode sizeMode = mWindow->SizeMode();
+
+    if (sizeMode != nsSizeMode_Minimized) {
+      if (sizeMode == nsSizeMode_Maximized)
+        sizeString.Assign(SIZEMODE_MAXIMIZED);
+      else if (sizeMode == nsSizeMode_Fullscreen)
+        sizeString.Assign(SIZEMODE_FULLSCREEN);
+      else
+        sizeString.Assign(SIZEMODE_NORMAL);
+      docShellElement->SetAttribute(MODE_ATTRIBUTE, sizeString, rv);
+      if (shouldPersist && persistString.Find("sizemode") >= 0) {
+        ownerXULDoc->Persist(windowElementId, MODE_ATTRIBUTE);
+      }
+    }
+    if (persistString.Find("zlevel") >= 0) {
+      uint32_t zLevel;
+      nsCOMPtr<nsIWindowMediator> mediator(do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+      if (mediator) {
+        mediator->GetZLevel(this, &zLevel);
+        SprintfLiteral(sizeBuf, "%" PRIu32, zLevel);
+        sizeString.AssignWithConversion(sizeBuf);
+        docShellElement->SetAttribute(ZLEVEL_ATTRIBUTE, sizeString, rv);
+        if (shouldPersist) {
+          ownerXULDoc->Persist(windowElementId, ZLEVEL_ATTRIBUTE);
+        }
+      }
+    }
+  }
+
+  mPersistentAttributesDirty = 0;
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetWindowDOMWindow(mozIDOMWindowProxy** aDOMWindow)
+{
+  NS_ENSURE_STATE(mDocShell);
+
+  if (!mDOMWindow)
+    mDOMWindow = mDocShell->GetWindow();
+  NS_ENSURE_TRUE(mDOMWindow, NS_ERROR_FAILURE);
+
+  *aDOMWindow = mDOMWindow;
+  NS_ADDREF(*aDOMWindow);
+  return NS_OK;
+}
+
+dom::Element*
+nsXULWindow::GetWindowDOMElement() const
+{
+  NS_ENSURE_TRUE(mDocShell, nullptr);
+
+  nsCOMPtr<nsIContentViewer> cv;
+  mDocShell->GetContentViewer(getter_AddRefs(cv));
+  NS_ENSURE_TRUE(cv, nullptr);
+
+  const nsIDocument* document = cv->GetDocument();
+  NS_ENSURE_TRUE(document, nullptr);
+
+  return document->GetRootElement();
+}
+
+nsresult nsXULWindow::ContentShellAdded(nsIDocShellTreeItem* aContentShell,
+   bool aPrimary, bool aTargetable, const nsAString& aID)
+{
+  nsContentShellInfo* shellInfo = nullptr;
+
+  uint32_t i, count = mContentShells.Length();
+  nsWeakPtr contentShellWeak = do_GetWeakReference(aContentShell);
+  for (i = 0; i < count; i++) {
+    nsContentShellInfo* info = mContentShells.ElementAt(i);
+    if (info->id.Equals(aID)) {
+      // We already exist. Do a replace.
+      info->child = contentShellWeak;
+      shellInfo = info;
+    }
+    else if (info->child == contentShellWeak)
+      info->child = nullptr;
+  }
+
+  if (!shellInfo) {
+    shellInfo = new nsContentShellInfo(aID, contentShellWeak);
+    mContentShells.AppendElement(shellInfo);
+  }
+    
+  // Set the default content tree owner
+  if (aPrimary) {
+    NS_ENSURE_SUCCESS(EnsurePrimaryContentTreeOwner(), NS_ERROR_FAILURE);
+    aContentShell->SetTreeOwner(mPrimaryContentTreeOwner);
+    mPrimaryContentShell = aContentShell;
+    mPrimaryTabParent = nullptr;
+  }
+  else {
+    NS_ENSURE_SUCCESS(EnsureContentTreeOwner(), NS_ERROR_FAILURE);
+    aContentShell->SetTreeOwner(mContentTreeOwner);
+    if (mPrimaryContentShell == aContentShell)
+      mPrimaryContentShell = nullptr;
+  }
+
+  if (aTargetable) {
+#ifdef DEBUG
+    int32_t debugCount = mTargetableShells.Count();
+    int32_t debugCounter;
+    for (debugCounter = debugCount - 1; debugCounter >= 0; --debugCounter) {
+      nsCOMPtr<nsIDocShellTreeItem> curItem =
+        do_QueryReferent(mTargetableShells[debugCounter]);
+      NS_ASSERTION(!SameCOMIdentity(curItem, aContentShell),
+                   "Adding already existing item to mTargetableShells");
+    }
+#endif
+    
+    // put the new shell at the start of the targetable shells list if either
+    // it's the new primary shell or there is no existing primary shell (which
+    // means that chances are this one just stopped being primary).  If we
+    // really cared, we could keep track of the "last no longer primary shell"
+    // explicitly, but it probably doesn't matter enough: the difference would
+    // only be felt in a situation where all shells were non-primary, which
+    // doesn't happen much.  In a situation where there is one and only one
+    // primary shell, and in which shells get unmarked as primary before some
+    // other shell gets marked as primary, this effectively stores the list of
+    // targetable shells in "most recently primary first" order.
+    bool inserted;
+    if (aPrimary || !mPrimaryContentShell) {
+      inserted = mTargetableShells.InsertObjectAt(contentShellWeak, 0);
+    } else {
+      inserted = mTargetableShells.AppendObject(contentShellWeak);
+    }
+    NS_ENSURE_TRUE(inserted, NS_ERROR_OUT_OF_MEMORY);
+  }
+
+  return NS_OK;
+}
+
+nsresult nsXULWindow::ContentShellRemoved(nsIDocShellTreeItem* aContentShell)
+{
+  if (mPrimaryContentShell == aContentShell) {
+    mPrimaryContentShell = nullptr;
+  }
+
+  int32_t i, count = mContentShells.Length();
+  for (i = count - 1; i >= 0; --i) {
+    nsContentShellInfo* info = mContentShells.ElementAt(i);
+    nsCOMPtr<nsIDocShellTreeItem> curItem = do_QueryReferent(info->child);
+    if (!curItem || SameCOMIdentity(curItem, aContentShell)) {
+      mContentShells.RemoveElementAt(i);
+      delete info;
+    }
+  }
+
+  count = mTargetableShells.Count();
+  for (i = count - 1; i >= 0; --i) {
+    nsCOMPtr<nsIDocShellTreeItem> curItem =
+      do_QueryReferent(mTargetableShells[i]);
+    if (!curItem || SameCOMIdentity(curItem, aContentShell)) {
+      mTargetableShells.RemoveObjectAt(i);
+    }
+  }
+  
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsXULWindow::GetPrimaryContentSize(int32_t* aWidth,
+                                   int32_t* aHeight)
+{
+  if (mPrimaryTabParent) {
+    return GetPrimaryTabParentSize(aWidth, aHeight);
+  } else if (mPrimaryContentShell) {
+    return GetPrimaryContentShellSize(aWidth, aHeight);
+  }
+  return NS_ERROR_UNEXPECTED;
+}
+
+nsresult
+nsXULWindow::GetPrimaryTabParentSize(int32_t* aWidth,
+                                     int32_t* aHeight)
+{
+  TabParent* tabParent = TabParent::GetFrom(mPrimaryTabParent);
+  // Need strong ref, since Client* can run script.
+  nsCOMPtr<Element> element = tabParent->GetOwnerElement();
+  NS_ENSURE_STATE(element);
+
+  *aWidth = element->ClientWidth();
+  *aHeight = element->ClientHeight();
+  return NS_OK;
+}
+
+nsresult
+nsXULWindow::GetPrimaryContentShellSize(int32_t* aWidth,
+                                        int32_t* aHeight)
+{
+  NS_ENSURE_STATE(mPrimaryContentShell);
+
+  nsCOMPtr<nsIBaseWindow> shellWindow(do_QueryInterface(mPrimaryContentShell));
+  NS_ENSURE_STATE(shellWindow);
+
+  int32_t devicePixelWidth, devicePixelHeight;
+  double shellScale = 1.0;
+  // We want to return CSS pixels. First, we get device pixels
+  // from the content area...
+  shellWindow->GetSize(&devicePixelWidth, &devicePixelHeight);
+  // And then get the device pixel scaling factor. Dividing device
+  // pixels by this scaling factor gives us CSS pixels.
+  shellWindow->GetUnscaledDevicePixelsPerCSSPixel(&shellScale);
+  *aWidth = NSToIntRound(devicePixelWidth / shellScale);
+  *aHeight = NSToIntRound(devicePixelHeight / shellScale);
+  return NS_OK;
+}
+
+NS_IMETHODIMP
+nsXULWindow::SetPrimaryContentSize(int32_t aWidth,
+                                   int32_t aHeight)
+{
+  if (mPrimaryTabParent) {
+    return SetPrimaryTabParentSize(aWidth, aHeight);
+  } else if (mPrimaryContentShell) {
+    return SizeShellTo(mPrimaryContentShell, aWidth, aHeight);
+  }
+  return NS_ERROR_UNEXPECTED;
+}
+
+nsresult
+nsXULWindow::SetPrimaryTabParentSize(int32_t aWidth,
+                                     int32_t aHeight)
+{
+  int32_t shellWidth, shellHeight;
+  GetPrimaryTabParentSize(&shellWidth, &shellHeight);
+
+  double scale = 1.0;
+  GetUnscaledDevicePixelsPerCSSPixel(&scale);
+
+  SizeShellToWithLimit(aWidth, aHeight,
+                       shellWidth * scale, shellHeight * scale);
+  return NS_OK;
+}
+
+nsresult
+nsXULWindow::GetRootShellSize(int32_t* aWidth,
+                              int32_t* aHeight)
+{
+  nsCOMPtr<nsIBaseWindow> shellAsWin = do_QueryInterface(mDocShell);
+  NS_ENSURE_TRUE(shellAsWin, NS_ERROR_FAILURE);
+  return shellAsWin->GetSize(aWidth, aHeight);
+}
+
+nsresult
+nsXULWindow::SetRootShellSize(int32_t aWidth,
+                              int32_t aHeight)
+{
+  nsCOMPtr<nsIDocShellTreeItem> docShellAsItem = do_QueryInterface(mDocShell);
+  return SizeShellTo(docShellAsItem, aWidth, aHeight);
+}
+
+NS_IMETHODIMP nsXULWindow::SizeShellTo(nsIDocShellTreeItem* aShellItem,
+   int32_t aCX, int32_t aCY)
+{
+  // XXXTAB This is wrong, we should actually reflow based on the passed in
+  // shell.  For now we are hacking and doing delta sizing.  This is bad
+  // because it assumes all size we add will go to the shell which probably
+  // won't happen.
+
+  nsCOMPtr<nsIBaseWindow> shellAsWin(do_QueryInterface(aShellItem));
+  NS_ENSURE_TRUE(shellAsWin, NS_ERROR_FAILURE);
+
+  int32_t width = 0;
+  int32_t height = 0;
+  shellAsWin->GetSize(&width, &height);
+
+  SizeShellToWithLimit(aCX, aCY, width, height);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::ExitModalLoop(nsresult aStatus)
+{
+  if (mContinueModalLoop)
+    EnableParent(true);
+  mContinueModalLoop = false;
+  mModalStatus = aStatus;
+  return NS_OK;
+}
+
+// top-level function to create a new window
+NS_IMETHODIMP nsXULWindow::CreateNewWindow(int32_t aChromeFlags,
+                                           nsITabParent *aOpeningTab,
+                                           mozIDOMWindowProxy *aOpener,
+                                           nsIXULWindow **_retval)
+{
+  NS_ENSURE_ARG_POINTER(_retval);
+
+  if (aChromeFlags & nsIWebBrowserChrome::CHROME_OPENAS_CHROME)
+    return CreateNewChromeWindow(aChromeFlags, aOpeningTab, aOpener, _retval);
+  return CreateNewContentWindow(aChromeFlags, aOpeningTab, aOpener, _retval);
+}
+
+NS_IMETHODIMP nsXULWindow::CreateNewChromeWindow(int32_t aChromeFlags,
+                                                 nsITabParent *aOpeningTab,
+                                                 mozIDOMWindowProxy *aOpener,
+                                                 nsIXULWindow **_retval)
+{
+  nsCOMPtr<nsIAppShellService> appShell(do_GetService(NS_APPSHELLSERVICE_CONTRACTID));
+  NS_ENSURE_TRUE(appShell, NS_ERROR_FAILURE);
+
+  // Just do a normal create of a window and return.
+  nsCOMPtr<nsIXULWindow> newWindow;
+  appShell->CreateTopLevelWindow(this, nullptr, aChromeFlags,
+                                 nsIAppShellService::SIZE_TO_CONTENT,
+                                 nsIAppShellService::SIZE_TO_CONTENT,
+                                 aOpeningTab, aOpener,
+                                 getter_AddRefs(newWindow));
+
+  NS_ENSURE_TRUE(newWindow, NS_ERROR_FAILURE);
+
+  *_retval = newWindow;
+  NS_ADDREF(*_retval);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::CreateNewContentWindow(int32_t aChromeFlags,
+                                                  nsITabParent *aOpeningTab,
+                                                  mozIDOMWindowProxy *aOpener,
+                                                  nsIXULWindow **_retval)
+{
+  nsCOMPtr<nsIAppShellService> appShell(do_GetService(NS_APPSHELLSERVICE_CONTRACTID));
+  NS_ENSURE_TRUE(appShell, NS_ERROR_FAILURE);
+
+  // We need to create a new top level window and then enter a nested
+  // loop. Eventually the new window will be told that it has loaded,
+  // at which time we know it is safe to spin out of the nested loop
+  // and allow the opening code to proceed.
+
+  nsCOMPtr<nsIURI> uri;
+
+  nsAdoptingCString urlStr = Preferences::GetCString("browser.chromeURL");
+  if (urlStr.IsEmpty()) {
+    urlStr.AssignLiteral("chrome://navigator/content/navigator.xul");
+  }
+
+  nsCOMPtr<nsIIOService> service(do_GetService(NS_IOSERVICE_CONTRACTID));
+  if (service) {
+    service->NewURI(urlStr, nullptr, nullptr, getter_AddRefs(uri));
+  }
+  NS_ENSURE_TRUE(uri, NS_ERROR_FAILURE);
+
+  // We need to create a chrome window to contain the content window we're about
+  // to pass back. The subject principal needs to be system while we're creating
+  // it to make things work right, so force a system caller. See bug 799348
+  // comment 13 for a description of what happens when we don't.
+  nsCOMPtr<nsIXULWindow> newWindow;
+  {
+    AutoNoJSAPI nojsapi;
+    // We actually want this toplevel window which we are creating to have a
+    // null opener, as we will be creating the content xul:browser window inside
+    // of it, so we pass nullptr as our aOpener.
+    appShell->CreateTopLevelWindow(this, uri,
+                                   aChromeFlags, 615, 480,
+                                   aOpeningTab, nullptr,
+                                   getter_AddRefs(newWindow));
+    NS_ENSURE_TRUE(newWindow, NS_ERROR_FAILURE);
+  }
+
+  // Specify that we want the window to remain locked until the chrome has loaded.
+  nsXULWindow *xulWin = static_cast<nsXULWindow*>
+                                   (static_cast<nsIXULWindow*>
+                                               (newWindow));
+
+  if (aOpener) {
+    nsCOMPtr<nsIDocShell> docShell;
+    xulWin->GetDocShell(getter_AddRefs(docShell));
+    MOZ_ASSERT(docShell);
+    nsCOMPtr<nsIDOMChromeWindow> chromeWindow =
+      do_QueryInterface(docShell->GetWindow());
+    MOZ_ASSERT(chromeWindow);
+
+    chromeWindow->SetOpenerForInitialContentBrowser(aOpener);
+  }
+
+  xulWin->LockUntilChromeLoad();
+
+  {
+    AutoNoJSAPI nojsapi;
+    nsIThread *thread = NS_GetCurrentThread();
+    while (xulWin->IsLocked()) {
+      if (!NS_ProcessNextEvent(thread))
+        break;
+    }
+  }
+
+  NS_ENSURE_STATE(xulWin->mPrimaryContentShell || xulWin->mPrimaryTabParent);
+
+  *_retval = newWindow;
+  NS_ADDREF(*_retval);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetHasPrimaryContent(bool* aResult)
+{
+  *aResult = mPrimaryTabParent || mPrimaryContentShell;
+  return NS_OK;
+}
+
+void nsXULWindow::EnableParent(bool aEnable)
+{
+  nsCOMPtr<nsIBaseWindow> parentWindow;
+  nsCOMPtr<nsIWidget>     parentWidget;
+
+  parentWindow = do_QueryReferent(mParentWindow);
+  if (parentWindow)
+    parentWindow->GetMainWidget(getter_AddRefs(parentWidget));
+  if (parentWidget)
+    parentWidget->Enable(aEnable);
+}
+
+// Constrain the window to its proper z-level
+bool nsXULWindow::ConstrainToZLevel(bool        aImmediate,
+                                      nsWindowZ  *aPlacement,
+                                      nsIWidget  *aReqBelow,
+                                      nsIWidget **aActualBelow)
+{
+#if 0
+  /* Do we have a parent window? This means our z-order is already constrained,
+     since we're a dependent window. Our window list isn't hierarchical,
+     so we can't properly calculate placement for such a window.
+     Should we just abort? */
+  nsCOMPtr<nsIBaseWindow> parentWindow = do_QueryReferent(mParentWindow);
+  if (parentWindow)
+    return false;
+#endif
+
+  nsCOMPtr<nsIWindowMediator> mediator(do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+  if (!mediator)
+    return false;
+
+  bool           altered;
+  uint32_t       position,
+                 newPosition,
+                 zLevel;
+  nsIXULWindow  *us = this;
+
+  altered = false;
+  mediator->GetZLevel(this, &zLevel);
+
+  // translate from WidgetGUIEvent to nsIWindowMediator constants
+  position = nsIWindowMediator::zLevelTop;
+  if (*aPlacement == nsWindowZBottom || zLevel == nsIXULWindow::lowestZ)
+    position = nsIWindowMediator::zLevelBottom;
+  else if (*aPlacement == nsWindowZRelative)
+    position = nsIWindowMediator::zLevelBelow;
+
+  if (NS_SUCCEEDED(mediator->CalculateZPosition(us, position, aReqBelow,
+                               &newPosition, aActualBelow, &altered))) {
+    /* If we were asked to move to the top but constrained to remain
+       below one of our other windows, first move all windows in that
+       window's layer and above to the top. This allows the user to
+       click a window which can't be topmost and still bring mozilla
+       to the foreground. */
+    if (altered &&
+        (position == nsIWindowMediator::zLevelTop ||
+         (position == nsIWindowMediator::zLevelBelow && aReqBelow == 0)))
+      PlaceWindowLayersBehind(zLevel + 1, nsIXULWindow::highestZ, 0);
+
+    if (*aPlacement != nsWindowZBottom &&
+        position == nsIWindowMediator::zLevelBottom)
+      altered = true;
+    if (altered || aImmediate) {
+      if (newPosition == nsIWindowMediator::zLevelTop)
+        *aPlacement = nsWindowZTop;
+      else if (newPosition == nsIWindowMediator::zLevelBottom)
+        *aPlacement = nsWindowZBottom;
+      else
+        *aPlacement = nsWindowZRelative;
+
+      if (aImmediate) {
+        nsCOMPtr<nsIBaseWindow> ourBase = do_QueryObject(this);
+        if (ourBase) {
+          nsCOMPtr<nsIWidget> ourWidget;
+          ourBase->GetMainWidget(getter_AddRefs(ourWidget));
+          ourWidget->PlaceBehind(*aPlacement == nsWindowZBottom ?
+                                   eZPlacementBottom : eZPlacementBelow,
+                                 *aActualBelow, false);
+        }
+      }
+    }
+
+    /* CalculateZPosition can tell us to be below nothing, because it tries
+       not to change something it doesn't recognize. A request to verify
+       being below an unrecognized window, then, is treated as a request
+       to come to the top (below null) */
+    nsCOMPtr<nsIXULWindow> windowAbove;
+    if (newPosition == nsIWindowMediator::zLevelBelow && *aActualBelow) {
+      windowAbove = (*aActualBelow)->GetWidgetListener()->GetXULWindow();
+    }
+
+    mediator->SetZPosition(us, newPosition, windowAbove);
+  }
+
+  return altered;
+}
+
+/* Re-z-position all windows in the layers from aLowLevel to aHighLevel,
+   inclusive, to be behind aBehind. aBehind of null means on top.
+   Note this method actually does nothing to our relative window positions.
+   (And therefore there's no need to inform WindowMediator we're moving
+   things, because we aren't.) This method is useful for, say, moving
+   a range of layers of our own windows relative to windows belonging to
+   external applications.
+*/
+void nsXULWindow::PlaceWindowLayersBehind(uint32_t aLowLevel,
+                                          uint32_t aHighLevel,
+                                          nsIXULWindow *aBehind)
+{
+  // step through windows in z-order from top to bottommost window
+
+  nsCOMPtr<nsIWindowMediator> mediator(do_GetService(NS_WINDOWMEDIATOR_CONTRACTID));
+  if (!mediator)
+    return;
+
+  nsCOMPtr<nsISimpleEnumerator> windowEnumerator;
+  mediator->GetZOrderXULWindowEnumerator(0, true,
+              getter_AddRefs(windowEnumerator));
+  if (!windowEnumerator)
+    return;
+
+  // each window will be moved behind previousHighWidget, itself
+  // a moving target. initialize it.
+  nsCOMPtr<nsIWidget> previousHighWidget;
+  if (aBehind) {
+    nsCOMPtr<nsIBaseWindow> highBase(do_QueryInterface(aBehind));
+    if (highBase)
+      highBase->GetMainWidget(getter_AddRefs(previousHighWidget));
+  }
+
+  // get next lower window
+  bool more;
+  while (windowEnumerator->HasMoreElements(&more), more) {
+    uint32_t nextZ; // z-level of nextWindow
+    nsCOMPtr<nsISupports> nextWindow;
+    windowEnumerator->GetNext(getter_AddRefs(nextWindow));
+    nsCOMPtr<nsIXULWindow> nextXULWindow(do_QueryInterface(nextWindow));
+    nextXULWindow->GetZLevel(&nextZ);
+    if (nextZ < aLowLevel)
+      break; // we've processed all windows through aLowLevel
+    
+    // move it just below its next higher window
+    nsCOMPtr<nsIBaseWindow> nextBase(do_QueryInterface(nextXULWindow));
+    if (nextBase) {
+      nsCOMPtr<nsIWidget> nextWidget;
+      nextBase->GetMainWidget(getter_AddRefs(nextWidget));
+      if (nextZ <= aHighLevel)
+        nextWidget->PlaceBehind(eZPlacementBelow, previousHighWidget, false);
+      previousHighWidget = nextWidget;
+    }
+  }
+}
+
+void nsXULWindow::SetContentScrollbarVisibility(bool aVisible)
+{
+  nsCOMPtr<nsPIDOMWindowOuter> contentWin(do_GetInterface(mPrimaryContentShell));
+  if (!contentWin) {
+    return;
+  }
+
+  nsContentUtils::SetScrollbarsVisibility(contentWin->GetDocShell(), aVisible);
+}
+
+bool nsXULWindow::GetContentScrollbarVisibility()
+{
+  // This code already exists in dom/src/base/nsBarProp.cpp, but we
+  // can't safely get to that from here as this function is called
+  // while the DOM window is being set up, and we need the DOM window
+  // to get to that code.
+  nsCOMPtr<nsIScrollable> scroller(do_QueryInterface(mPrimaryContentShell));
+
+  if (scroller) {
+    int32_t prefValue;
+    scroller->GetDefaultScrollbarPreferences(
+                  nsIScrollable::ScrollOrientation_Y, &prefValue);
+    if (prefValue == nsIScrollable::Scrollbar_Never) // try the other way
+      scroller->GetDefaultScrollbarPreferences(
+                  nsIScrollable::ScrollOrientation_X, &prefValue);
+
+    if (prefValue == nsIScrollable::Scrollbar_Never)
+      return false;
+  }
+
+  return true;
+}
+
+// during spinup, attributes that haven't been loaded yet can't be dirty
+void nsXULWindow::PersistentAttributesDirty(uint32_t aDirtyFlags)
+{
+  mPersistentAttributesDirty |= aDirtyFlags & mPersistentAttributesMask;
+}
+
+NS_IMETHODIMP nsXULWindow::ApplyChromeFlags()
+{
+  nsCOMPtr<dom::Element> window = GetWindowDOMElement();
+  NS_ENSURE_TRUE(window, NS_ERROR_FAILURE);
+
+  if (mChromeLoaded) {
+    // The two calls in this block don't need to happen early because they
+    // don't cause a global restyle on the document.  Not only that, but the
+    // scrollbar stuff needs a content area to toggle the scrollbars on anyway.
+    // So just don't do these until mChromeLoaded is true.
+
+    // Scrollbars have their own special treatment.
+    SetContentScrollbarVisibility(mChromeFlags &
+                                  nsIWebBrowserChrome::CHROME_SCROLLBARS ?
+                                    true : false);
+  }
+
+  /* the other flags are handled together. we have style rules
+     in navigator.css that trigger visibility based on
+     the 'chromehidden' attribute of the <window> tag. */
+  nsAutoString newvalue;
+
+  if (! (mChromeFlags & nsIWebBrowserChrome::CHROME_MENUBAR))
+    newvalue.AppendLiteral("menubar ");
+
+  if (! (mChromeFlags & nsIWebBrowserChrome::CHROME_TOOLBAR))
+    newvalue.AppendLiteral("toolbar ");
+
+  if (! (mChromeFlags & nsIWebBrowserChrome::CHROME_LOCATIONBAR))
+    newvalue.AppendLiteral("location ");
+
+  if (! (mChromeFlags & nsIWebBrowserChrome::CHROME_PERSONAL_TOOLBAR))
+    newvalue.AppendLiteral("directories ");
+
+  if (! (mChromeFlags & nsIWebBrowserChrome::CHROME_STATUSBAR))
+    newvalue.AppendLiteral("status ");
+
+  if (! (mChromeFlags & nsIWebBrowserChrome::CHROME_EXTRA))
+    newvalue.AppendLiteral("extrachrome ");
+
+  // Note that if we're not actually changing the value this will be a no-op,
+  // so no need to compare to the old value.
+  ErrorResult rv;
+  window->SetAttribute(NS_LITERAL_STRING("chromehidden"), newvalue, rv);
+
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::GetXULBrowserWindow(nsIXULBrowserWindow * *aXULBrowserWindow)
+{
+  NS_IF_ADDREF(*aXULBrowserWindow = mXULBrowserWindow);
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsXULWindow::SetXULBrowserWindow(nsIXULBrowserWindow * aXULBrowserWindow)
+{
+  mXULBrowserWindow = aXULBrowserWindow;
+  return NS_OK;
+}
+
+void nsXULWindow::SizeShellToWithLimit(int32_t aDesiredWidth,
+                                       int32_t aDesiredHeight,
+                                       int32_t shellItemWidth,
+                                       int32_t shellItemHeight)
+{
+  int32_t widthDelta = aDesiredWidth - shellItemWidth;
+  int32_t heightDelta = aDesiredHeight - shellItemHeight;
+
+  if (widthDelta || heightDelta) {
+    int32_t winWidth = 0;
+    int32_t winHeight = 0;
+
+    GetSize(&winWidth, &winHeight);
+    // There's no point in trying to make the window smaller than the
+    // desired content area size --- that's not likely to work. This whole
+    // function assumes that the outer docshell is adding some constant
+    // "border" chrome to the content area.
+    winWidth = std::max(winWidth + widthDelta, aDesiredWidth);
+    winHeight = std::max(winHeight + heightDelta, aDesiredHeight);
+    SetSize(winWidth, winHeight, true);
+  }
+}
+
+//*****************************************************************************
+//*** nsContentShellInfo: Object Management
+//*****************************************************************************   
+
+nsContentShellInfo::nsContentShellInfo(const nsAString& aID,
+                                       nsIWeakReference* aContentShell)
+  : id(aID),
+    child(aContentShell)
+{
+  MOZ_COUNT_CTOR(nsContentShellInfo);
+}
+
+nsContentShellInfo::~nsContentShellInfo()
+{
+  MOZ_COUNT_DTOR(nsContentShellInfo);
+   //XXX Set Tree Owner to null if the tree owner is nsXULWindow->mContentTreeOwner
+} 
diff --git a/xpfe/appshell/nsXULWindow.h b/xpfe/appshell/nsXULWindow.h
new file mode 100644
index 000000000..eb059c939
--- /dev/null
+++ b/xpfe/appshell/nsXULWindow.h
@@ -0,0 +1,199 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#ifndef nsXULWindow_h__
+#define nsXULWindow_h__
+
+// Local Includes
+#include "nsChromeTreeOwner.h"
+#include "nsContentTreeOwner.h"
+
+// Helper classes
+#include "nsCOMPtr.h"
+#include "nsTArray.h"
+#include "nsString.h"
+#include "nsWeakReference.h"
+#include "nsCOMArray.h"
+#include "nsRect.h"
+#include "Units.h"
+
+// Interfaces needed
+#include "nsIBaseWindow.h"
+#include "nsIDocShell.h"
+#include "nsIDocShellTreeItem.h"
+#include "nsIDOMWindow.h"
+#include "nsIInterfaceRequestor.h"
+#include "nsIInterfaceRequestorUtils.h"
+#include "nsIXULWindow.h"
+#include "nsIPrompt.h"
+#include "nsIAuthPrompt.h"
+#include "nsIXULBrowserWindow.h"
+#include "nsIWeakReference.h"
+#include "nsIWidgetListener.h"
+#include "nsITabParent.h"
+
+namespace mozilla {
+namespace dom {
+class Element;
+} // namespace dom
+} // namespace mozilla
+
+// nsXULWindow
+
+#define NS_XULWINDOW_IMPL_CID                         \
+{ /* 8eaec2f3-ed02-4be2-8e0f-342798477298 */          \
+     0x8eaec2f3,                                      \
+     0xed02,                                          \
+     0x4be2,                                          \
+   { 0x8e, 0x0f, 0x34, 0x27, 0x98, 0x47, 0x72, 0x98 } \
+}
+
+class nsContentShellInfo;
+
+class nsXULWindow : public nsIBaseWindow,
+                    public nsIInterfaceRequestor,
+                    public nsIXULWindow,
+                    public nsSupportsWeakReference
+{
+friend class nsChromeTreeOwner;
+friend class nsContentTreeOwner;
+
+public:
+   NS_DECL_THREADSAFE_ISUPPORTS
+
+   NS_DECL_NSIINTERFACEREQUESTOR
+   NS_DECL_NSIXULWINDOW
+   NS_DECL_NSIBASEWINDOW
+
+   NS_DECLARE_STATIC_IID_ACCESSOR(NS_XULWINDOW_IMPL_CID)
+
+   void LockUntilChromeLoad() { mLockedUntilChromeLoad = true; }
+   bool IsLocked() const { return mLockedUntilChromeLoad; }
+   void IgnoreXULSizeMode(bool aEnable) { mIgnoreXULSizeMode = aEnable; }
+   void WasRegistered() { mRegistered = true; }
+
+protected:
+   enum persistentAttributes {
+     PAD_MISC =         0x1,
+     PAD_POSITION =     0x2,
+     PAD_SIZE =         0x4
+   };
+
+   explicit nsXULWindow(uint32_t aChromeFlags);
+   virtual ~nsXULWindow();
+
+   NS_IMETHOD EnsureChromeTreeOwner();
+   NS_IMETHOD EnsureContentTreeOwner();
+   NS_IMETHOD EnsurePrimaryContentTreeOwner();
+   NS_IMETHOD EnsurePrompter();
+   NS_IMETHOD EnsureAuthPrompter();
+
+   void OnChromeLoaded();
+   void StaggerPosition(int32_t &aRequestedX, int32_t &aRequestedY,
+                        int32_t aSpecWidth, int32_t aSpecHeight);
+   bool       LoadPositionFromXUL(int32_t aSpecWidth, int32_t aSpecHeight);
+   bool       LoadSizeFromXUL(int32_t& aSpecWidth, int32_t& aSpecHeight);
+   void       SetSpecifiedSize(int32_t aSpecWidth, int32_t aSpecHeight);
+   bool       LoadMiscPersistentAttributesFromXUL();
+   void       SyncAttributesToWidget();
+   NS_IMETHOD SavePersistentAttributes();
+
+   NS_IMETHOD GetWindowDOMWindow(mozIDOMWindowProxy** aDOMWindow);
+   mozilla::dom::Element* GetWindowDOMElement() const;
+
+   // See nsIDocShellTreeOwner for docs on next two methods
+   nsresult ContentShellAdded(nsIDocShellTreeItem* aContentShell,
+                                          bool aPrimary, bool aTargetable,
+                                          const nsAString& aID);
+   nsresult ContentShellRemoved(nsIDocShellTreeItem* aContentShell);
+   NS_IMETHOD GetPrimaryContentSize(int32_t* aWidth,
+                                    int32_t* aHeight);
+   NS_IMETHOD SetPrimaryContentSize(int32_t aWidth,
+                                    int32_t aHeight);
+   nsresult GetRootShellSize(int32_t* aWidth,
+                             int32_t* aHeight);
+   nsresult SetRootShellSize(int32_t aWidth,
+                             int32_t aHeight);
+
+   NS_IMETHOD SizeShellTo(nsIDocShellTreeItem* aShellItem, int32_t aCX, 
+      int32_t aCY);
+   NS_IMETHOD ExitModalLoop(nsresult aStatus);
+   NS_IMETHOD CreateNewChromeWindow(int32_t aChromeFlags, nsITabParent* aOpeningTab, mozIDOMWindowProxy* aOpenerWindow, nsIXULWindow **_retval);
+   NS_IMETHOD CreateNewContentWindow(int32_t aChromeFlags, nsITabParent* aOpeningTab, mozIDOMWindowProxy* aOpenerWindow, nsIXULWindow **_retval);
+   NS_IMETHOD GetHasPrimaryContent(bool* aResult);
+
+   void       EnableParent(bool aEnable);
+   bool       ConstrainToZLevel(bool aImmediate, nsWindowZ *aPlacement,
+                                nsIWidget *aReqBelow, nsIWidget **aActualBelow);
+   void       PlaceWindowLayersBehind(uint32_t aLowLevel, uint32_t aHighLevel,
+                                      nsIXULWindow *aBehind);
+   void       SetContentScrollbarVisibility(bool aVisible);
+   bool       GetContentScrollbarVisibility();
+   void       PersistentAttributesDirty(uint32_t aDirtyFlags);
+
+   nsChromeTreeOwner*      mChromeTreeOwner;
+   nsContentTreeOwner*     mContentTreeOwner;
+   nsContentTreeOwner*     mPrimaryContentTreeOwner;
+   nsCOMPtr<nsIWidget>     mWindow;
+   nsCOMPtr<nsIDocShell>   mDocShell;
+   nsCOMPtr<nsPIDOMWindowOuter>  mDOMWindow;
+   nsCOMPtr<nsIWeakReference> mParentWindow;
+   nsCOMPtr<nsIPrompt>     mPrompter;
+   nsCOMPtr<nsIAuthPrompt> mAuthPrompter;
+   nsCOMPtr<nsIXULBrowserWindow> mXULBrowserWindow;
+   nsCOMPtr<nsIDocShellTreeItem> mPrimaryContentShell;
+   nsTArray<nsContentShellInfo*> mContentShells; // array of doc shells by id
+   nsresult                mModalStatus;
+   bool                    mContinueModalLoop;
+   bool                    mDebuting;       // being made visible right now
+   bool                    mChromeLoaded; // True when chrome has loaded
+   bool                    mShowAfterLoad;
+   bool                    mIntrinsicallySized; 
+   bool                    mCenterAfterLoad;
+   bool                    mIsHiddenWindow;
+   bool                    mLockedUntilChromeLoad;
+   bool                    mIgnoreXULSize;
+   bool                    mIgnoreXULPosition;
+   bool                    mChromeFlagsFrozen;
+   bool                    mIgnoreXULSizeMode;
+   // mDestroying is used to prevent reentry into into Destroy(), which can
+   // otherwise happen due to script running as we tear down various things.
+   bool                    mDestroying;
+   bool                    mRegistered;
+   uint32_t                mContextFlags;
+   uint32_t                mPersistentAttributesDirty; // persistentAttributes
+   uint32_t                mPersistentAttributesMask;
+   uint32_t                mChromeFlags;
+   nsString                mTitle;
+   nsIntRect               mOpenerScreenRect; // the screen rect of the opener
+
+   nsCOMArray<nsIWeakReference> mTargetableShells; // targetable shells only
+
+   nsCOMPtr<nsITabParent> mPrimaryTabParent;
+private:
+   nsresult GetPrimaryTabParentSize(int32_t* aWidth, int32_t* aHeight);
+   nsresult GetPrimaryContentShellSize(int32_t* aWidth, int32_t* aHeight);
+   nsresult SetPrimaryTabParentSize(int32_t aWidth, int32_t aHeight);
+};
+
+NS_DEFINE_STATIC_IID_ACCESSOR(nsXULWindow, NS_XULWINDOW_IMPL_CID)
+
+// nsContentShellInfo
+// Used to map shell IDs to nsIDocShellTreeItems.
+
+class nsContentShellInfo
+{
+public:
+   nsContentShellInfo(const nsAString& aID,
+                      nsIWeakReference* aContentShell);
+   ~nsContentShellInfo();
+
+public:
+   nsString id; // The identifier of the content shell
+   nsWeakPtr child; // content shell (weak reference to nsIDocShellTreeItem)
+};
+
+#endif /* nsXULWindow_h__ */
diff --git a/xpfe/appshell/test/chrome.ini b/xpfe/appshell/test/chrome.ini
new file mode 100644
index 000000000..6f4b72829
--- /dev/null
+++ b/xpfe/appshell/test/chrome.ini
@@ -0,0 +1,5 @@
+[DEFAULT]
+skip-if = os == 'android'
+
+[test_hiddenPrivateWindow.xul]
+[test_windowlessBrowser.xul]
diff --git a/xpfe/appshell/test/test_hiddenPrivateWindow.xul b/xpfe/appshell/test/test_hiddenPrivateWindow.xul
new file mode 100644
index 000000000..a1dfb486d
--- /dev/null
+++ b/xpfe/appshell/test/test_hiddenPrivateWindow.xul
@@ -0,0 +1,45 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=815847
+-->
+<window title="Mozilla Bug 815847"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js" />
+
+<body  xmlns="http://www.w3.org/1999/xhtml">
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=815847">Mozilla Bug 815847</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+</pre>
+</body>
+
+<script class="testbody" type="application/javascript">
+<![CDATA[
+
+var Cu = Components.utils;
+
+Cu.import('resource://gre/modules/Services.jsm');
+Cu.import('resource://gre/modules/PrivateBrowsingUtils.jsm');
+
+ok(Services.appShell.hiddenWindow, "hiddenWindow should exist");
+ok(Services.appShell.hiddenDOMWindow, "hiddenDOMWindow should exist");
+ok(Services.appShell.hiddenPrivateWindow, "hiddenPrivateWindow should exist");
+ok(Services.appShell.hiddenPrivateDOMWindow, "hiddenPrivateDOMWindow should exist");
+
+ok(!PrivateBrowsingUtils.isWindowPrivate(Services.appShell.hiddenWindow.docShell), "hiddenWindow should not be private");
+ok(!PrivateBrowsingUtils.isWindowPrivate(Services.appShell.hiddenDOMWindow), "hiddenDOMWindow should not be private");
+ok(PrivateBrowsingUtils.isWindowPrivate(Services.appShell.hiddenPrivateWindow.docShell), "hiddenPrivateWindow should be private");
+ok(PrivateBrowsingUtils.isWindowPrivate(Services.appShell.hiddenPrivateDOMWindow), "hiddenPrivateDOMWindow should be private");
+
+]]>
+</script>
+
+</window>
diff --git a/xpfe/appshell/test/test_windowlessBrowser.xul b/xpfe/appshell/test/test_windowlessBrowser.xul
new file mode 100644
index 000000000..ef91f7655
--- /dev/null
+++ b/xpfe/appshell/test/test_windowlessBrowser.xul
@@ -0,0 +1,75 @@
+<?xml version="1.0"?>
+<?xml-stylesheet href="chrome://global/skin" type="text/css"?>
+<?xml-stylesheet href="chrome://mochikit/content/tests/SimpleTest/test.css"
+                 type="text/css"?>
+<!--
+https://bugzilla.mozilla.org/show_bug.cgi?id=815847
+-->
+<window title="Mozilla Bug 815847"
+  xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
+
+  <script type="application/javascript"
+          src="chrome://mochikit/content/tests/SimpleTest/SimpleTest.js" />
+
+<body  xmlns="http://www.w3.org/1999/xhtml">
+<a target="_blank" href="https://bugzilla.mozilla.org/show_bug.cgi?id=1214174">Mozilla Bug 1214174</a>
+<p id="display"></p>
+<div id="content" style="display: none">
+
+</div>
+<pre id="test">
+</pre>
+</body>
+
+<script class="testbody" type="application/javascript">
+<![CDATA[
+
+var Cu = Components.utils;
+var Ci = Components.interfaces;
+
+Cu.import('resource://gre/modules/Services.jsm');
+
+function testWindowlessBrowser(chromePrivileged) {
+  var webNav = Services.appShell.createWindowlessBrowser(chromePrivileged);
+
+  ok(webNav, "createWindowlessBrowser should return a wevNav");
+
+  let interfaceRequestor = webNav.QueryInterface(Ci.nsIInterfaceRequestor);
+  let docShell = interfaceRequestor.getInterface(Ci.nsIDocShell);
+
+  ok(docShell, "docShell should be defined");
+  ok(docShell.contentViewer.DOMDocument.defaultView, "docShell defaultView should be defined");
+
+  var win = docShell.contentViewer.DOMDocument.defaultView;
+
+  ok(win.screenX == 0, "window.screenX should be 0 in a windowless browser");
+  ok(win.screenY == 0, "window.screenY should be 0 in a windowless browser");
+  ok(win.outerWidth == 0, "window.outerWidth should be 0 in a windowless browser");
+  ok(win.outerHeight == 0, "window.outerHeight should be 0 in a windowless browser");
+  
+  ok(win.sidebar, "window.sidebar should be defined");
+  ok(win.external, "window.external should be defined");
+  
+  var exception;
+
+  try {
+    win.external.AddSearchProvider("http://test-fake.url");
+  } catch(e) {
+    exception = e;
+  }
+  
+  ok(!exception, "window.external.AddSearchProvider should be ignore withour raising an exception");
+
+  webNav.close();
+}
+
+info("Test Bug 1214174 on a content privileged windowless browser");
+testWindowlessBrowser(false);
+
+info("Test Bug 1214174 on a chrome privileged windowless browser");
+testWindowlessBrowser(true);
+
+]]>
+</script>
+
+</window>