Merge branch 'master' of https://github.com/MoonchildProductions/UXP into _testBranch_test_1

48 files changed, 925 insertions, 786 deletions

diff --git a/dom/base/DOMIntersectionObserver.cpp b/dom/base/DOMIntersectionObserver.cpp
index 169c3fe7a..e39abf1a6 100644
--- a/dom/base/DOMIntersectionObserver.cpp
+++ b/dom/base/DOMIntersectionObserver.cpp
@@ -47,6 +47,7 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(DOMIntersectionObserver)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mCallback)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mRoot)
   NS_IMPL_CYCLE_COLLECTION_UNLINK(mQueuedEntries)
+  tmp->Disconnect();
 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
 
 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(DOMIntersectionObserver)
@@ -184,9 +185,10 @@ DOMIntersectionObserver::Connect()
   if (mConnected) {
     return;
   }
+  mConnected = true;
+
   nsIDocument* document = mOwner->GetExtantDoc();
   document->AddIntersectionObserver(this);
-  mConnected = true;
 }
 
 void
@@ -202,7 +204,9 @@ DOMIntersectionObserver::Disconnect()
   mObservationTargets.Clear();
   if (mOwner) {
     nsIDocument* document = mOwner->GetExtantDoc();
-    document->RemoveIntersectionObserver(this);
+    if (document) {
+      document->RemoveIntersectionObserver(this);
+    }
   }
   mConnected = false;
 }
@@ -248,6 +252,12 @@ EdgeInclusiveIntersection(const nsRect& aRect, const nsRect& aOtherRect)
   return Some(nsRect(left, top, right - left, bottom - top));
 }
 
+enum class BrowsingContextInfo {
+  SimilarOriginBrowsingContext,
+  DifferentOriginBrowsingContext,
+  UnknownBrowsingContext
+};
+
 void
 DOMIntersectionObserver::Update(nsIDocument* aDocument, DOMHighResTimeStamp time)
 {
@@ -359,11 +369,22 @@ DOMIntersectionObserver::Update(nsIDocument* aDocument, DOMHighResTimeStamp time
       }
     }
 
-    nsRect rootIntersectionRect = rootRect;
-    bool isInSimilarOriginBrowsingContext = rootFrame && targetFrame &&
-                                            CheckSimilarOrigin(root, target);
+    nsRect rootIntersectionRect;
+    BrowsingContextInfo isInSimilarOriginBrowsingContext =
+      BrowsingContextInfo::UnknownBrowsingContext;
+
+    if (rootFrame && targetFrame) {
+      rootIntersectionRect = rootRect;
+    }
+ 
+    if (root && target) {
+      isInSimilarOriginBrowsingContext = CheckSimilarOrigin(root, target) ?
+        BrowsingContextInfo::SimilarOriginBrowsingContext :
+        BrowsingContextInfo::DifferentOriginBrowsingContext;
+    }
 
-    if (isInSimilarOriginBrowsingContext) {
+    if (isInSimilarOriginBrowsingContext ==
+        BrowsingContextInfo::SimilarOriginBrowsingContext) {
       rootIntersectionRect.Inflate(rootMargin);
     }
 
@@ -413,7 +434,9 @@ DOMIntersectionObserver::Update(nsIDocument* aDocument, DOMHighResTimeStamp time
     if (target->UpdateIntersectionObservation(this, threshold)) {
       QueueIntersectionObserverEntry(
         target, time,
-        isInSimilarOriginBrowsingContext ? Some(rootIntersectionRect) : Nothing(),
+        isInSimilarOriginBrowsingContext ==
+          BrowsingContextInfo::DifferentOriginBrowsingContext ?
+          Nothing() : Some(rootIntersectionRect),
         targetRect, intersectionRect, intersectionRatio
       );
     }
diff --git a/dom/base/DOMIntersectionObserver.h b/dom/base/DOMIntersectionObserver.h
index 3eb10ad38..8144fc5c5 100644
--- a/dom/base/DOMIntersectionObserver.h
+++ b/dom/base/DOMIntersectionObserver.h
@@ -101,9 +101,7 @@ protected:
 class DOMIntersectionObserver final : public nsISupports,
                                       public nsWrapperCache
 {
-  virtual ~DOMIntersectionObserver() {
-    Disconnect();
-  }
+  virtual ~DOMIntersectionObserver() { }
 
 public:
   DOMIntersectionObserver(already_AddRefed<nsPIDOMWindowInner>&& aOwner,
diff --git a/dom/base/Element.cpp b/dom/base/Element.cpp
index 9ced64c0d..52d06b0f8 100644
--- a/dom/base/Element.cpp
+++ b/dom/base/Element.cpp
@@ -183,6 +183,12 @@ Element::DoGetClasses() const
 NS_IMETHODIMP
 Element::QueryInterface(REFNSIID aIID, void** aInstancePtr)
 {
+  if (aIID.Equals(NS_GET_IID(Element))) {
+    NS_ADDREF_THIS();
+    *aInstancePtr = this;
+    return NS_OK;
+  }
+
   NS_ASSERTION(aInstancePtr,
                "QueryInterface requires a non-NULL destination!");
   nsresult rv = FragmentOrElement::QueryInterface(aIID, aInstancePtr);
@@ -1838,6 +1844,24 @@ Element::UnbindFromTree(bool aDeep, bool aNullParent)
     SetParentIsContent(false);
   }
 
+#ifdef DEBUG
+  // If we can get access to the PresContext, then we sanity-check that
+  // we're not leaving behind a pointer to ourselves as the PresContext's
+  // cached provider of the viewport's scrollbar styles.
+  if (document) {
+    nsIPresShell* presShell = document->GetShell();
+    if (presShell) {
+      nsPresContext* presContext = presShell->GetPresContext();
+      if (presContext) {
+        MOZ_ASSERT(this !=
+                   presContext->GetViewportScrollbarStylesOverrideNode(),
+                   "Leaving behind a raw pointer to this node (as having "
+                   "propagated scrollbar styles) - that's dangerous...");
+      }
+    }
+  }
+#endif
+
   // Ensure that CSS transitions don't continue on an element at a
   // different place in the tree (even if reinserted before next
   // animation refresh).
@@ -3888,44 +3912,55 @@ Element::ClearDataset()
   slots->mDataset = nullptr;
 }
 
-nsTArray<Element::nsDOMSlots::IntersectionObserverRegistration>*
+nsDataHashtable<nsPtrHashKey<DOMIntersectionObserver>, int32_t>*
 Element::RegisteredIntersectionObservers()
 {
   nsDOMSlots* slots = DOMSlots();
   return &slots->mRegisteredIntersectionObservers;
 }
 
+enum nsPreviousIntersectionThreshold {
+  eUninitialized = -2,
+  eNonIntersecting = -1
+};
+
 void
 Element::RegisterIntersectionObserver(DOMIntersectionObserver* aObserver)
 {
-  RegisteredIntersectionObservers()->AppendElement(
-    nsDOMSlots::IntersectionObserverRegistration { aObserver, -1 });
+  nsDataHashtable<nsPtrHashKey<DOMIntersectionObserver>, int32_t>* observers =
+    RegisteredIntersectionObservers();
+  if (observers->Contains(aObserver)) {
+    return;
+  }
+
+  // Value can be:
+  //   -2:   Makes sure next calculated threshold always differs, leading to a
+  //         notification task being scheduled.
+  //   -1:   Non-intersecting.
+  //   >= 0: Intersecting, valid index of aObserver->mThresholds.
+  RegisteredIntersectionObservers()->Put(aObserver, eUninitialized);
 }
 
 void
 Element::UnregisterIntersectionObserver(DOMIntersectionObserver* aObserver)
 {
-  nsTArray<nsDOMSlots::IntersectionObserverRegistration>* observers =
+  nsDataHashtable<nsPtrHashKey<DOMIntersectionObserver>, int32_t>* observers =
     RegisteredIntersectionObservers();
-  for (uint32_t i = 0; i < observers->Length(); ++i) {
-    nsDOMSlots::IntersectionObserverRegistration reg = observers->ElementAt(i);
-    if (reg.observer == aObserver) {
-      observers->RemoveElementAt(i);
-      break;
-    }
-  }
+  observers->Remove(aObserver);
 }
 
 bool
 Element::UpdateIntersectionObservation(DOMIntersectionObserver* aObserver, int32_t aThreshold)
 {
-  nsTArray<nsDOMSlots::IntersectionObserverRegistration>* observers =
+  nsDataHashtable<nsPtrHashKey<DOMIntersectionObserver>, int32_t>* observers =
     RegisteredIntersectionObservers();
-  for (auto& reg : *observers) {
-    if (reg.observer == aObserver && reg.previousThreshold != aThreshold) {
-      reg.previousThreshold = aThreshold;
-      return true;
-    }
+  if (!observers->Contains(aObserver)) {
+    return false;
+  }
+  int32_t previousThreshold = observers->Get(aObserver);
+  if (previousThreshold != aThreshold) {
+    observers->Put(aObserver, aThreshold);
+    return true;
   }
   return false;
 }
diff --git a/dom/base/Element.h b/dom/base/Element.h
index cf1d197e2..049984d1b 100644
--- a/dom/base/Element.h
+++ b/dom/base/Element.h
@@ -1380,7 +1380,7 @@ protected:
   nsDOMTokenList* GetTokenList(nsIAtom* aAtom,
                                const DOMTokenListSupportedTokenArray aSupportedTokens = nullptr);
 
-  nsTArray<nsDOMSlots::IntersectionObserverRegistration>* RegisteredIntersectionObservers();
+  nsDataHashtable<nsPtrHashKey<DOMIntersectionObserver>, int32_t>* RegisteredIntersectionObservers();
 
 private:
   /**
diff --git a/dom/base/File.cpp b/dom/base/File.cpp
index 8602a3064..7d86dfe8a 100755
--- a/dom/base/File.cpp
+++ b/dom/base/File.cpp
@@ -912,7 +912,7 @@ BlobImplFile::GetType(nsAString& aType)
         new GetTypeRunnable(workerPrivate, this);
 
       ErrorResult rv;
-      runnable->Dispatch(rv);
+      runnable->Dispatch(Terminating, rv);
       if (NS_WARN_IF(rv.Failed())) {
         rv.SuppressException();
       }
diff --git a/dom/base/FragmentOrElement.cpp b/dom/base/FragmentOrElement.cpp
index 79f6cff51..fde983e7c 100644
--- a/dom/base/FragmentOrElement.cpp
+++ b/dom/base/FragmentOrElement.cpp
@@ -608,6 +608,7 @@ FragmentOrElement::nsDOMSlots::Unlink(bool aIsXUL)
   mLabelsList = nullptr;
   mCustomElementData = nullptr;
   mClassList = nullptr;
+  mRegisteredIntersectionObservers.Clear();
 }
 
 size_t
@@ -1359,6 +1360,13 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(FragmentOrElement)
   {
     nsDOMSlots *slots = tmp->GetExistingDOMSlots();
     if (slots) {
+      if (tmp->IsElement()) {
+        Element* elem = tmp->AsElement();
+        for (auto iter = slots->mRegisteredIntersectionObservers.Iter(); !iter.Done(); iter.Next()) {
+          DOMIntersectionObserver* observer = iter.Key();
+          observer->UnlinkTarget(*elem);
+        }
+      }
       slots->Unlink(tmp->IsXULElement());
     }
   }
@@ -1937,7 +1945,6 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
 NS_INTERFACE_MAP_BEGIN(FragmentOrElement)
   NS_WRAPPERCACHE_INTERFACE_MAP_ENTRY
   NS_INTERFACE_MAP_ENTRIES_CYCLE_COLLECTION(FragmentOrElement)
-  NS_INTERFACE_MAP_ENTRY(Element)
   NS_INTERFACE_MAP_ENTRY(nsIContent)
   NS_INTERFACE_MAP_ENTRY(nsINode)
   NS_INTERFACE_MAP_ENTRY(nsIDOMEventTarget)
diff --git a/dom/base/FragmentOrElement.h b/dom/base/FragmentOrElement.h
index 1cd8033bb..7c74e9cd4 100644
--- a/dom/base/FragmentOrElement.h
+++ b/dom/base/FragmentOrElement.h
@@ -21,6 +21,7 @@
 #include "nsIWeakReference.h"             // base class
 #include "nsNodeUtils.h"                  // class member nsNodeUtils::CloneNodeImpl
 #include "nsIHTMLCollection.h"
+#include "nsDataHashtable.h"
 
 class ContentUnbinder;
 class nsContentList;
@@ -353,12 +354,7 @@ public:
     /**
      * Registered Intersection Observers on the element.
      */
-    struct IntersectionObserverRegistration {
-      DOMIntersectionObserver* observer;
-      int32_t previousThreshold;
-    };
-
-    nsTArray<IntersectionObserverRegistration> mRegisteredIntersectionObservers;
+    nsDataHashtable<nsPtrHashKey<DOMIntersectionObserver>, int32_t> mRegisteredIntersectionObservers;
   };
 
 protected:
diff --git a/dom/base/IdleRequest.cpp b/dom/base/IdleRequest.cpp
index 26190f98b..fb3983d37 100644
--- a/dom/base/IdleRequest.cpp
+++ b/dom/base/IdleRequest.cpp
@@ -9,7 +9,6 @@
 #include "mozilla/Function.h"
 #include "mozilla/TimeStamp.h"
 #include "mozilla/dom/IdleDeadline.h"
-#include "mozilla/dom/Performance.h"
 #include "mozilla/dom/PerformanceTiming.h"
 #include "mozilla/dom/WindowBinding.h"
 #include "nsComponentManagerUtils.h"
@@ -20,138 +19,56 @@
 namespace mozilla {
 namespace dom {
 
-IdleRequest::IdleRequest(JSContext* aCx, nsPIDOMWindowInner* aWindow,
-                         IdleRequestCallback& aCallback, uint32_t aHandle)
-  : mWindow(aWindow)
-  , mCallback(&aCallback)
+IdleRequest::IdleRequest(IdleRequestCallback* aCallback, uint32_t aHandle)
+  : mCallback(aCallback)
   , mHandle(aHandle)
   , mTimeoutHandle(Nothing())
 {
-  MOZ_ASSERT(aWindow);
-
-  // Get the calling location.
-  nsJSUtils::GetCallingLocation(aCx, mFileName, &mLineNo, &mColumn);
+  MOZ_DIAGNOSTIC_ASSERT(mCallback);
 }
 
 IdleRequest::~IdleRequest()
 {
 }
 
-NS_IMPL_CYCLE_COLLECTION_CLASS(IdleRequest)
+NS_IMPL_CYCLE_COLLECTION(IdleRequest, mCallback)
 
 NS_IMPL_CYCLE_COLLECTING_ADDREF(IdleRequest)
 NS_IMPL_CYCLE_COLLECTING_RELEASE(IdleRequest)
 
-NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(IdleRequest)
-  NS_IMPL_CYCLE_COLLECTION_UNLINK(mWindow)
-  NS_IMPL_CYCLE_COLLECTION_UNLINK(mCallback)
-NS_IMPL_CYCLE_COLLECTION_UNLINK_END
-
-NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(IdleRequest)
-  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mWindow)
-  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mCallback)
-NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
-
 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(IdleRequest)
-  NS_INTERFACE_MAP_ENTRY(nsIRunnable)
-  NS_INTERFACE_MAP_ENTRY(nsICancelableRunnable)
-  NS_INTERFACE_MAP_ENTRY(nsIIncrementalRunnable)
-  NS_INTERFACE_MAP_ENTRY(nsITimeoutHandler)
-  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsITimeoutHandler)
 NS_INTERFACE_MAP_END
 
-nsresult
-IdleRequest::SetTimeout(uint32_t aTimeout)
-{
-  int32_t handle;
-  nsresult rv = nsGlobalWindow::Cast(mWindow)->SetTimeoutOrInterval(
-    this, aTimeout, false, Timeout::Reason::eIdleCallbackTimeout, &handle);
-  mTimeoutHandle = Some(handle);
-
-  return rv;
-}
-
-nsresult
-IdleRequest::Run()
-{
-  if (mCallback) {
-    RunIdleRequestCallback(false);
-  }
-
-  return NS_OK;
-}
-
-nsresult
-IdleRequest::Cancel()
+void
+IdleRequest::SetTimeoutHandle(int32_t aHandle)
 {
-  mCallback = nullptr;
-  CancelTimeout();
-  if (isInList()) {
-    remove();
-  }
-  Release();
-
-  return NS_OK;
+  mTimeoutHandle = Some(aHandle);
 }
 
-void
-IdleRequest::SetDeadline(TimeStamp aDeadline)
+uint32_t
+IdleRequest::GetTimeoutHandle() const
 {
-  mozilla::dom::Performance* perf = mWindow->GetPerformance();
-  mDeadline =
-    perf ? perf->GetDOMTiming()->TimeStampToDOMHighRes(aDeadline) : 0.0;
+  MOZ_DIAGNOSTIC_ASSERT(mTimeoutHandle.isSome());
+  return mTimeoutHandle.value();
 }
 
 nsresult
-IdleRequest::RunIdleRequestCallback(bool aDidTimeout)
+IdleRequest::IdleRun(nsPIDOMWindowInner* aWindow,
+                     DOMHighResTimeStamp aDeadline,
+                     bool aDidTimeout)
 {
   MOZ_ASSERT(NS_IsMainThread());
+  MOZ_DIAGNOSTIC_ASSERT(mCallback);
 
-  if (!aDidTimeout) {
-    CancelTimeout();
-  }
-
-  remove();
   ErrorResult error;
   RefPtr<IdleDeadline> deadline =
-    new IdleDeadline(mWindow, aDidTimeout, mDeadline);
+    new IdleDeadline(aWindow, aDidTimeout, aDeadline);
   mCallback->Call(*deadline, error, "requestIdleCallback handler");
-  mCallback = nullptr;
-  Release();
 
+  mCallback = nullptr;
+  error.SuppressException();
   return error.StealNSResult();
 }
 
-void
-IdleRequest::CancelTimeout()
-{
-  if (mTimeoutHandle.isSome()) {
-    nsGlobalWindow::Cast(mWindow)->ClearTimeoutOrInterval(
-      mTimeoutHandle.value(), Timeout::Reason::eIdleCallbackTimeout);
-  }
-}
-
-nsresult
-IdleRequest::Call()
-{
-  SetDeadline(TimeStamp::Now());
-  return RunIdleRequestCallback(true);
-}
-
-void
-IdleRequest::GetLocation(const char** aFileName, uint32_t* aLineNo,
-                         uint32_t* aColumn)
-{
-  *aFileName = mFileName.get();
-  *aLineNo = mLineNo;
-  *aColumn = mColumn;
-}
-
-void
-IdleRequest::MarkForCC()
-{
-  mCallback->MarkForCC();
-}
-
 } // namespace dom
 } // namespace mozilla
diff --git a/dom/base/IdleRequest.h b/dom/base/IdleRequest.h
index cb234430a..acf56f852 100644
--- a/dom/base/IdleRequest.h
+++ b/dom/base/IdleRequest.h
@@ -12,7 +12,6 @@
 #include "nsCOMPtr.h"
 #include "nsCycleCollectionParticipant.h"
 #include "nsDOMNavigationTiming.h"
-#include "nsITimeoutHandler.h"
 
 class nsPIDOMWindowInner;
 
@@ -21,28 +20,19 @@ namespace dom {
 
 class IdleRequestCallback;
 
-class IdleRequest final : public nsITimeoutHandler
-                        , public nsIRunnable
-                        , public nsICancelableRunnable
-                        , public nsIIncrementalRunnable
-                        , public LinkedListElement<IdleRequest>
+class IdleRequest final : public nsISupports,
+                          public LinkedListElement<IdleRequest>
 {
 public:
-  IdleRequest(JSContext* aCx, nsPIDOMWindowInner* aWindow,
-              IdleRequestCallback& aCallback, uint32_t aHandle);
+  IdleRequest(IdleRequestCallback* aCallback, uint32_t aHandle);
 
-  virtual nsresult Call() override;
-  virtual void GetLocation(const char** aFileName, uint32_t* aLineNo,
-                           uint32_t* aColumn) override;
-  virtual void MarkForCC() override;
+  nsresult IdleRun(nsPIDOMWindowInner* aWindow,
+                   DOMHighResTimeStamp aDeadline,
+                   bool aDidTimeout);
 
-  nsresult SetTimeout(uint32_t aTimout);
-  nsresult RunIdleRequestCallback(bool aDidTimeout);
-  void CancelTimeout();
-
-  NS_DECL_NSIRUNNABLE;
-  virtual nsresult Cancel() override;
-  virtual void SetDeadline(mozilla::TimeStamp aDeadline) override;
+  void SetTimeoutHandle(int32_t aHandle);
+  bool HasTimeout() const { return mTimeoutHandle.isSome(); }
+  uint32_t GetTimeoutHandle() const;
 
   uint32_t Handle() const
   {
@@ -50,22 +40,14 @@ public:
   }
 
   NS_DECL_CYCLE_COLLECTING_ISUPPORTS
-  NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(IdleRequest, nsITimeoutHandler)
+  NS_DECL_CYCLE_COLLECTION_CLASS(IdleRequest)
 
 private:
   ~IdleRequest();
 
-  // filename, line number and JS language version string of the
-  // caller of setTimeout()
-  nsCString mFileName;
-  uint32_t mLineNo;
-  uint32_t mColumn;
-
-  nsCOMPtr<nsPIDOMWindowInner> mWindow;
   RefPtr<IdleRequestCallback> mCallback;
-  uint32_t mHandle;
+  const uint32_t mHandle;
   mozilla::Maybe<int32_t> mTimeoutHandle;
-  DOMHighResTimeStamp mDeadline;
 };
 
 } // namespace dom
diff --git a/dom/base/Location.cpp b/dom/base/Location.cpp
index e3b614931..7b3722f09 100644
--- a/dom/base/Location.cpp
+++ b/dom/base/Location.cpp
@@ -393,6 +393,10 @@ Location::GetHost(nsAString& aHost)
 NS_IMETHODIMP
 Location::SetHost(const nsAString& aHost)
 {
+  if (aHost.IsEmpty()) {
+    return NS_OK; // Ignore empty string
+  }
+
   nsCOMPtr<nsIURI> uri;
   nsresult rv = GetWritableURI(getter_AddRefs(uri));
   if (NS_WARN_IF(NS_FAILED(rv) || !uri)) {
@@ -424,6 +428,10 @@ Location::GetHostname(nsAString& aHostname)
 NS_IMETHODIMP
 Location::SetHostname(const nsAString& aHostname)
 {
+  if (aHostname.IsEmpty()) {
+    return NS_OK; // Ignore empty string
+  }
+
   nsCOMPtr<nsIURI> uri;
   nsresult rv = GetWritableURI(getter_AddRefs(uri));
   if (NS_WARN_IF(NS_FAILED(rv) || !uri)) {
@@ -507,6 +515,10 @@ nsresult
 Location::SetHrefWithBase(const nsAString& aHref, nsIURI* aBase,
                             bool aReplace)
 {
+  if (aHref.IsEmpty()) {
+    return NS_OK; // Ignore empty string
+  }
+
   nsresult result;
   nsCOMPtr<nsIURI> newUri;
 
@@ -577,19 +589,17 @@ Location::GetPathname(nsAString& aPathname)
   aPathname.Truncate();
 
   nsCOMPtr<nsIURI> uri;
-  nsresult result = NS_OK;
-
-  result = GetURI(getter_AddRefs(uri));
+  nsresult result = GetURI(getter_AddRefs(uri));
+  if (NS_FAILED(result) || !uri) {
+    return result;
+  }
 
-  nsCOMPtr<nsIURIWithQuery> url(do_QueryInterface(uri));
-  if (url) {
-    nsAutoCString file;
+  nsAutoCString file;
 
-    result = url->GetFilePath(file);
+  result = uri->GetFilePath(file);
 
-    if (NS_SUCCEEDED(result)) {
-      AppendUTF8toUTF16(file, aPathname);
-    }
+  if (NS_SUCCEEDED(result)) {
+    AppendUTF8toUTF16(file, aPathname);
   }
 
   return result;
@@ -604,8 +614,7 @@ Location::SetPathname(const nsAString& aPathname)
     return rv;
   }
 
-  nsCOMPtr<nsIURIWithQuery> url(do_QueryInterface(uri));
-  if (url && NS_SUCCEEDED(url->SetFilePath(NS_ConvertUTF16toUTF8(aPathname)))) {
+  if (NS_SUCCEEDED(uri->SetFilePath(NS_ConvertUTF16toUTF8(aPathname)))) {
     return SetURI(uri);
   }
 
@@ -697,6 +706,10 @@ Location::GetProtocol(nsAString& aProtocol)
 NS_IMETHODIMP
 Location::SetProtocol(const nsAString& aProtocol)
 {
+  if (aProtocol.IsEmpty()) {
+    return NS_OK; // Ignore empty string
+  }
+
   nsCOMPtr<nsIURI> uri;
   nsresult rv = GetWritableURI(getter_AddRefs(uri));
   if (NS_WARN_IF(NS_FAILED(rv) || !uri)) {
@@ -750,6 +763,10 @@ Location::GetSearch(nsAString& aSearch)
 NS_IMETHODIMP
 Location::SetSearch(const nsAString& aSearch)
 {
+  if (aSearch.IsEmpty()) {
+    return NS_OK; // Ignore empty string
+  }
+
   nsresult rv = SetSearchInternal(aSearch);
   if (NS_FAILED(rv)) {
     return rv;
diff --git a/dom/base/Navigator.cpp b/dom/base/Navigator.cpp
index 5c315517c..ed96ee23b 100644
--- a/dom/base/Navigator.cpp
+++ b/dom/base/Navigator.cpp
@@ -767,12 +767,6 @@ StaticRefPtr<VibrateWindowListener> gVibrateWindowListener;
 
 static bool
 MayVibrate(nsIDocument* doc) {
-#if MOZ_WIDGET_GONK
-  if (XRE_IsParentProcess()) {
-    return true; // The system app can always vibrate
-  }
-#endif // MOZ_WIDGET_GONK
-
   // Hidden documents cannot start or stop a vibration.
   return (doc && !doc->Hidden());
 }
diff --git a/dom/base/ScreenOrientation.cpp b/dom/base/ScreenOrientation.cpp
index bb3ccf5c3..ec9c4fa29 100644
--- a/dom/base/ScreenOrientation.cpp
+++ b/dom/base/ScreenOrientation.cpp
@@ -309,7 +309,7 @@ ScreenOrientation::LockInternal(ScreenOrientationInternal aOrientation, ErrorRes
     return nullptr;
   }
 
-#if !defined(MOZ_WIDGET_ANDROID) && !defined(MOZ_WIDGET_GONK)
+#if !defined(MOZ_WIDGET_ANDROID)
   // User agent does not support locking the screen orientation.
   p->MaybeReject(NS_ERROR_DOM_NOT_SUPPORTED_ERR);
   return p.forget();
diff --git a/dom/base/StructuredCloneHolder.cpp b/dom/base/StructuredCloneHolder.cpp
index 1c27c632e..8e7cee340 100644
--- a/dom/base/StructuredCloneHolder.cpp
+++ b/dom/base/StructuredCloneHolder.cpp
@@ -1075,9 +1075,9 @@ StructuredCloneHolder::CustomReadHandler(JSContext* aCx,
     return ReadFormData(aCx, aReader, aIndex, this);
   }
 
-  if (aTag == SCTAG_DOM_IMAGEBITMAP) {
-    MOZ_ASSERT(mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
-               mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread);
+  if (aTag == SCTAG_DOM_IMAGEBITMAP &&
+      (mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
+       mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread)) {
 
     // Get the current global object.
     // This can be null.
@@ -1087,7 +1087,9 @@ StructuredCloneHolder::CustomReadHandler(JSContext* aCx,
                                             parent, GetSurfaces(), aIndex);
   }
 
-  if (aTag == SCTAG_DOM_WASM) {
+  if (aTag == SCTAG_DOM_WASM &&
+      (mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
+       mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread)) {
     return ReadWasmModule(aCx, aIndex, this);
   }
 
@@ -1202,9 +1204,9 @@ StructuredCloneHolder::CustomReadTransferHandler(JSContext* aCx,
     return true;
   }
 
-  if (aTag == SCTAG_DOM_CANVAS) {
-    MOZ_ASSERT(mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
-               mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread);
+  if (aTag == SCTAG_DOM_CANVAS &&
+      (mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
+       mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread)) {
     MOZ_ASSERT(aContent);
     OffscreenCanvasCloneData* data =
       static_cast<OffscreenCanvasCloneData*>(aContent);
@@ -1222,9 +1224,9 @@ StructuredCloneHolder::CustomReadTransferHandler(JSContext* aCx,
     return true;
   }
 
-  if (aTag == SCTAG_DOM_IMAGEBITMAP) {
-    MOZ_ASSERT(mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
-               mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread);
+  if (aTag == SCTAG_DOM_IMAGEBITMAP &&
+      (mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
+       mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread)) {
     MOZ_ASSERT(aContent);
     ImageBitmapCloneData* data =
       static_cast<ImageBitmapCloneData*>(aContent);
@@ -1328,9 +1330,9 @@ StructuredCloneHolder::CustomFreeTransferHandler(uint32_t aTag,
     return;
   }
 
-  if (aTag == SCTAG_DOM_CANVAS) {
-    MOZ_ASSERT(mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
-               mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread);
+  if (aTag == SCTAG_DOM_CANVAS &&
+      (mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
+       mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread)) {
     MOZ_ASSERT(aContent);
     OffscreenCanvasCloneData* data =
       static_cast<OffscreenCanvasCloneData*>(aContent);
@@ -1338,9 +1340,9 @@ StructuredCloneHolder::CustomFreeTransferHandler(uint32_t aTag,
     return;
   }
 
-  if (aTag == SCTAG_DOM_IMAGEBITMAP) {
-    MOZ_ASSERT(mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
-               mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread);
+  if (aTag == SCTAG_DOM_IMAGEBITMAP &&
+      (mStructuredCloneScope == StructuredCloneScope::SameProcessSameThread ||
+       mStructuredCloneScope == StructuredCloneScope::SameProcessDifferentThread)) {
     MOZ_ASSERT(aContent);
     ImageBitmapCloneData* data =
       static_cast<ImageBitmapCloneData*>(aContent);
diff --git a/dom/base/Timeout.h b/dom/base/Timeout.h
index e929f3dd1..42e2f57f5 100644
--- a/dom/base/Timeout.h
+++ b/dom/base/Timeout.h
@@ -41,7 +41,11 @@ public:
   // default main thread being used.
   nsresult InitTimer(nsIEventTarget* aTarget, uint32_t aDelay);
 
-  enum class Reason { eTimeoutOrInterval, eIdleCallbackTimeout };
+  enum class Reason
+  {
+    eTimeoutOrInterval,
+    eIdleCallbackTimeout,
+  };
 
 #ifdef DEBUG
   bool HasRefCntOne() const;
@@ -62,6 +66,8 @@ public:
   // True if this is a repeating/interval timer
   bool mIsInterval;
 
+  // Used to allow several reasons for setting a timeout, where each
+  // 'Reason' value is using a possibly overlapping set of id:s.
   Reason mReason;
 
   // Returned as value of setTimeout()
diff --git a/dom/base/TimeoutHandler.cpp b/dom/base/TimeoutHandler.cpp
new file mode 100644
index 000000000..78c3f16dd
--- /dev/null
+++ b/dom/base/TimeoutHandler.cpp
@@ -0,0 +1,43 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim: set ts=8 sts=2 et sw=2 tw=80: */
+/* 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 "TimeoutHandler.h"
+
+namespace mozilla {
+namespace dom {
+
+TimeoutHandler::TimeoutHandler(JSContext* aCx)
+  : TimeoutHandler()
+{
+  nsJSUtils::GetCallingLocation(aCx, mFileName, &mLineNo, &mColumn);
+}
+
+nsresult
+TimeoutHandler::Call()
+{
+  return NS_OK;
+}
+
+void
+TimeoutHandler::GetLocation(const char** aFileName, uint32_t* aLineNo,
+                                    uint32_t* aColumn)
+{
+  *aFileName = mFileName.get();
+  *aLineNo = mLineNo;
+  *aColumn = mColumn;
+}
+
+NS_IMPL_CYCLE_COLLECTION_0(TimeoutHandler)
+
+NS_IMPL_CYCLE_COLLECTING_ADDREF(TimeoutHandler)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(TimeoutHandler)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(TimeoutHandler)
+  NS_INTERFACE_MAP_ENTRY(nsITimeoutHandler)
+NS_INTERFACE_MAP_END
+
+} // namespace dom
+} // namespace mozilla
diff --git a/dom/base/TimeoutHandler.h b/dom/base/TimeoutHandler.h
new file mode 100644
index 000000000..cb0a0ce94
--- /dev/null
+++ b/dom/base/TimeoutHandler.h
@@ -0,0 +1,50 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 mozilla_dom_timeout_handler_h
+#define mozilla_dom_timeout_handler_h
+
+#include "nsCOMPtr.h"
+#include "nsISupports.h"
+#include "nsITimeoutHandler.h"
+
+namespace mozilla {
+namespace dom {
+
+/**
+ * Utility class for implementing nsITimeoutHandlers, designed to be subclassed.
+ */
+class TimeoutHandler : public nsITimeoutHandler
+{
+public:
+  // TimeoutHandler doesn't actually contain cycles, but subclasses
+  // probably will.
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_CLASS(TimeoutHandler)
+
+  virtual nsresult Call() override;
+  virtual void GetLocation(const char** aFileName, uint32_t* aLineNo,
+                           uint32_t* aColumn) override;
+  virtual void MarkForCC() override {}
+protected:
+  TimeoutHandler() : mFileName(""), mLineNo(0), mColumn(0) {}
+  explicit TimeoutHandler(JSContext *aCx);
+
+  virtual ~TimeoutHandler() {}
+private:
+  TimeoutHandler(const TimeoutHandler&) = delete;
+  TimeoutHandler& operator=(const TimeoutHandler&) = delete;
+  TimeoutHandler& operator=(const TimeoutHandler&&) = delete;
+
+  nsCString mFileName;
+  uint32_t mLineNo;
+  uint32_t mColumn;
+};
+
+} // namespace dom
+} // namespace mozilla
+
+#endif // mozilla_dom_timeout_handler_h
diff --git a/dom/base/WebSocket.cpp b/dom/base/WebSocket.cpp
index d85bae82b..af4b7858b 100644
--- a/dom/base/WebSocket.cpp
+++ b/dom/base/WebSocket.cpp
@@ -340,7 +340,7 @@ WebSocketImpl::PrintErrorOnConsole(const char *aBundleURI,
       new PrintErrorOnConsoleRunnable(this, aBundleURI, aError, aFormatStrings,
                                       aFormatStringsLen);
     ErrorResult rv;
-    runnable->Dispatch(rv);
+    runnable->Dispatch(Killing, rv);
     // XXXbz this seems totally broken.  We should be propagating this out, but
     // none of our callers really propagate anything usefully.  Come to think of
     // it, why is this a syncrunnable anyway?  Can't this be a fire-and-forget
@@ -629,7 +629,7 @@ WebSocketImpl::Disconnect()
     RefPtr<DisconnectInternalRunnable> runnable =
       new DisconnectInternalRunnable(this);
     ErrorResult rv;
-    runnable->Dispatch(rv);
+    runnable->Dispatch(Killing, rv);
     // XXXbz this seems totally broken.  We should be propagating this out, but
     // where to, exactly?
     rv.SuppressException();
@@ -1293,7 +1293,7 @@ WebSocket::ConstructorCommon(const GlobalObject& aGlobal,
       new InitRunnable(webSocketImpl, !!aTransportProvider, aUrl,
                        protocolArray, nsDependentCString(file.get()), lineno,
                        column, aRv, &connectionFailed);
-    runnable->Dispatch(aRv);
+    runnable->Dispatch(Terminating, aRv);
   }
 
   if (NS_WARN_IF(aRv.Failed())) {
@@ -1377,7 +1377,7 @@ WebSocket::ConstructorCommon(const GlobalObject& aGlobal,
                "not yet implemented");
     RefPtr<AsyncOpenRunnable> runnable =
       new AsyncOpenRunnable(webSocket->mImpl, aRv);
-    runnable->Dispatch(aRv);
+    runnable->Dispatch(Terminating, aRv);
   }
 
   if (NS_WARN_IF(aRv.Failed())) {
diff --git a/dom/base/moz.build b/dom/base/moz.build
index 0fb345d22..77eb01ba6 100755
--- a/dom/base/moz.build
+++ b/dom/base/moz.build
@@ -217,6 +217,7 @@ EXPORTS.mozilla.dom += [
     'TabGroup.h',
     'Text.h',
     'Timeout.h',
+    'TimeoutHandler.h',
     'TreeWalker.h',
     'WebKitCSSMatrix.h',
     'WebSocket.h',
@@ -364,6 +365,7 @@ UNIFIED_SOURCES += [
     'TextInputProcessor.cpp',
     'ThirdPartyUtil.cpp',
     'Timeout.cpp',
+    'TimeoutHandler.cpp',
     'TimerClamping.cpp',
     'TreeWalker.cpp',
     'WebKitCSSMatrix.cpp',
@@ -460,11 +462,6 @@ LOCAL_INCLUDES += [
     '/xpcom/ds',
 ]
 
-if CONFIG['MOZ_WIDGET_TOOLKIT'] == 'gonk':
-    LOCAL_INCLUDES += [
-        '../system/gonk',
-    ]
-
 if CONFIG['MOZ_WEBRTC']:
     LOCAL_INCLUDES += [
         '/netwerk/sctp/datachannel',
diff --git a/dom/base/nsContentPermissionHelper.cpp b/dom/base/nsContentPermissionHelper.cpp
index fd04b1013..c57fc6233 100644
--- a/dom/base/nsContentPermissionHelper.cpp
+++ b/dom/base/nsContentPermissionHelper.cpp
@@ -5,9 +5,6 @@
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include <map>
-#ifdef MOZ_WIDGET_GONK
-#include "GonkPermission.h"
-#endif // MOZ_WIDGET_GONK
 #include "nsCOMPtr.h"
 #include "nsIDOMElement.h"
 #include "nsIPrincipal.h"
diff --git a/dom/base/nsContentPolicy.cpp b/dom/base/nsContentPolicy.cpp
index 337debcea..5511b9086 100644
--- a/dom/base/nsContentPolicy.cpp
+++ b/dom/base/nsContentPolicy.cpp
@@ -20,6 +20,7 @@
 #include "nsIDOMElement.h"
 #include "nsIDOMNode.h"
 #include "nsIDOMWindow.h"
+#include "nsITabChild.h"
 #include "nsIContent.h"
 #include "nsILoadContext.h"
 #include "nsCOMArray.h"
@@ -89,8 +90,9 @@ nsContentPolicy::CheckPolicy(CPMethod          policyMethod,
     {
         nsCOMPtr<nsIDOMNode> node(do_QueryInterface(requestingContext));
         nsCOMPtr<nsIDOMWindow> window(do_QueryInterface(requestingContext));
-        NS_ASSERTION(!requestingContext || node || window,
-                     "Context should be a DOM node or a DOM window!");
+        nsCOMPtr<nsITabChild> tabChild(do_QueryInterface(requestingContext));
+        NS_ASSERTION(!requestingContext || node || window || tabChild,
+                     "Context should be a DOM node, DOM window or a tabChild!");
     }
 #endif
 
diff --git a/dom/base/nsContentPolicyUtils.h b/dom/base/nsContentPolicyUtils.h
index ed0544226..600b24c56 100644
--- a/dom/base/nsContentPolicyUtils.h
+++ b/dom/base/nsContentPolicyUtils.h
@@ -134,6 +134,7 @@ NS_CP_ContentTypeName(uint32_t contentType)
     CASE_RETURN( TYPE_INTERNAL_IMAGE_FAVICON      );
     CASE_RETURN( TYPE_INTERNAL_STYLESHEET         );
     CASE_RETURN( TYPE_INTERNAL_STYLESHEET_PRELOAD );
+    CASE_RETURN( TYPE_SAVEAS_DOWNLOAD             );
    default:
     return "<Unknown Type>";
   }
diff --git a/dom/base/nsContentUtils.cpp b/dom/base/nsContentUtils.cpp
index ef87a250e..34c7d23b8 100644
--- a/dom/base/nsContentUtils.cpp
+++ b/dom/base/nsContentUtils.cpp
@@ -281,6 +281,7 @@ bool nsContentUtils::sIsCutCopyAllowed = true;
 bool nsContentUtils::sIsFrameTimingPrefEnabled = false;
 bool nsContentUtils::sIsPerformanceTimingEnabled = false;
 bool nsContentUtils::sIsResourceTimingEnabled = false;
+bool nsContentUtils::sIsPerformanceNavigationTimingEnabled = false;
 bool nsContentUtils::sIsUserTimingLoggingEnabled = false;
 bool nsContentUtils::sIsExperimentalAutocompleteEnabled = false;
 bool nsContentUtils::sEncodeDecodeURLHash = false;
@@ -571,6 +572,9 @@ nsContentUtils::Init()
   Preferences::AddBoolVarCache(&sIsResourceTimingEnabled,
                                "dom.enable_resource_timing", true);
 
+  Preferences::AddBoolVarCache(&sIsPerformanceNavigationTimingEnabled,
+                               "dom.enable_performance_navigation_timing", true);
+
   Preferences::AddBoolVarCache(&sIsUserTimingLoggingEnabled,
                                "dom.performance.enable_user_timing_logging", false);
 
@@ -5100,7 +5104,7 @@ nsContentUtils::TriggerLink(nsIContent *aContent, nsPresContext *aPresContext,
 
     handler->OnLinkClick(aContent, aLinkURI,
                          fileName.IsVoid() ? aTargetSpec.get() : EmptyString().get(),
-                         fileName, nullptr, nullptr, aIsTrusted);
+                         fileName, nullptr, nullptr, aIsTrusted, aContent->NodePrincipal());
   }
 }
 
@@ -9772,9 +9776,13 @@ nsContentUtils::AttemptLargeAllocationLoad(nsIHttpChannel* aChannel)
   rv = aChannel->GetReferrer(getter_AddRefs(referrer));
   NS_ENSURE_SUCCESS(rv, false);
 
+  nsCOMPtr<nsILoadInfo> loadInfo = aChannel->GetLoadInfo();
+  nsCOMPtr<nsIPrincipal> triggeringPrincipal = loadInfo->TriggeringPrincipal();
+
   // Actually perform the cross process load
   bool reloadSucceeded = false;
-  rv = wbc3->ReloadInFreshProcess(docShell, uri, referrer, &reloadSucceeded);
+  rv = wbc3->ReloadInFreshProcess(docShell, uri, referrer,
+                                  triggeringPrincipal, &reloadSucceeded);
   NS_ENSURE_SUCCESS(rv, false);
 
   return reloadSucceeded;
diff --git a/dom/base/nsContentUtils.h b/dom/base/nsContentUtils.h
index 0932f451e..9ae6d2155 100644
--- a/dom/base/nsContentUtils.h
+++ b/dom/base/nsContentUtils.h
@@ -2033,6 +2033,14 @@ public:
   }
 
   /*
+   * Returns true if the performance timing APIs are enabled.
+   */
+  static bool IsPerformanceNavigationTimingEnabled()
+  {
+    return sIsPerformanceNavigationTimingEnabled;
+  }
+
+  /*
    * Returns true if notification should be sent for peformance timing events.
    */
   static bool SendPerformanceTimingNotifications()
@@ -2825,6 +2833,7 @@ private:
   static uint32_t sHandlingInputTimeout;
   static bool sIsPerformanceTimingEnabled;
   static bool sIsResourceTimingEnabled;
+  static bool sIsPerformanceNavigationTimingEnabled;
   static bool sIsUserTimingLoggingEnabled;
   static bool sIsFrameTimingPrefEnabled;
   static bool sIsExperimentalAutocompleteEnabled;
diff --git a/dom/base/nsDOMNavigationTiming.cpp b/dom/base/nsDOMNavigationTiming.cpp
index 31b2932fb..32ce8a8cb 100644
--- a/dom/base/nsDOMNavigationTiming.cpp
+++ b/dom/base/nsDOMNavigationTiming.cpp
@@ -15,6 +15,9 @@
 #include "nsPrintfCString.h"
 #include "mozilla/dom/PerformanceNavigation.h"
 #include "mozilla/TimeStamp.h"
+#include "mozilla/Telemetry.h"
+
+using namespace mozilla;
 
 nsDOMNavigationTiming::nsDOMNavigationTiming()
 {
@@ -30,47 +33,36 @@ nsDOMNavigationTiming::Clear()
 {
   mNavigationType = TYPE_RESERVED;
   mNavigationStartHighRes = 0;
-  mBeforeUnloadStart = 0;
-  mUnloadStart = 0;
-  mUnloadEnd = 0;
-  mLoadEventStart = 0;
-  mLoadEventEnd = 0;
-  mDOMLoading = 0;
-  mDOMInteractive = 0;
-  mDOMContentLoadedEventStart = 0;
-  mDOMContentLoadedEventEnd = 0;
-  mDOMComplete = 0;
-
-  mLoadEventStartSet = false;
-  mLoadEventEndSet = false;
-  mDOMLoadingSet = false;
-  mDOMInteractiveSet = false;
-  mDOMContentLoadedEventStartSet = false;
-  mDOMContentLoadedEventEndSet = false;
-  mDOMCompleteSet = false;
+  mBeforeUnloadStart = TimeStamp();
+  mUnloadStart = TimeStamp();
+  mUnloadEnd = TimeStamp();
+  mLoadEventStart = TimeStamp();
+  mLoadEventEnd = TimeStamp();
+  mDOMLoading = TimeStamp();
+  mDOMInteractive = TimeStamp();
+  mDOMContentLoadedEventStart = TimeStamp();
+  mDOMContentLoadedEventEnd = TimeStamp();
+  mDOMComplete = TimeStamp();
+
   mDocShellHasBeenActiveSinceNavigationStart = false;
 }
 
 DOMTimeMilliSec
-nsDOMNavigationTiming::TimeStampToDOM(mozilla::TimeStamp aStamp) const
+nsDOMNavigationTiming::TimeStampToDOM(TimeStamp aStamp) const
 {
   if (aStamp.IsNull()) {
     return 0;
   }
-  mozilla::TimeDuration duration = aStamp - mNavigationStartTimeStamp;
-  return GetNavigationStart() + static_cast<int64_t>(duration.ToMilliseconds());
-}
 
-DOMTimeMilliSec nsDOMNavigationTiming::DurationFromStart()
-{
-  return TimeStampToDOM(mozilla::TimeStamp::Now());
+  TimeDuration duration = aStamp - mNavigationStart;
+  return GetNavigationStart() + static_cast<int64_t>(duration.ToMilliseconds());
 }
 
 void
 nsDOMNavigationTiming::NotifyNavigationStart(DocShellState aDocShellState)
 {
   mNavigationStartHighRes = (double)PR_Now() / PR_USEC_PER_MSEC;
-  mNavigationStartTimeStamp = mozilla::TimeStamp::Now();
+  mNavigationStart = TimeStamp::Now();
   mDocShellHasBeenActiveSinceNavigationStart = (aDocShellState == DocShellState::eActive);
 }
 
@@ -86,7 +78,7 @@ nsDOMNavigationTiming::NotifyFetchStart(nsIURI* aURI, Type aNavigationType)
 void
 nsDOMNavigationTiming::NotifyBeforeUnload()
 {
-  mBeforeUnloadStart = DurationFromStart();
+  mBeforeUnloadStart = TimeStamp::Now();
 }
 
 void
@@ -99,105 +91,107 @@ nsDOMNavigationTiming::NotifyUnloadAccepted(nsIURI* aOldURI)
 void
 nsDOMNavigationTiming::NotifyUnloadEventStart()
 {
-  mUnloadStart = DurationFromStart();
+  mUnloadStart = TimeStamp::Now();
 }
 
 void
 nsDOMNavigationTiming::NotifyUnloadEventEnd()
 {
-  mUnloadEnd = DurationFromStart();
+  mUnloadEnd = TimeStamp::Now();
 }
 
 void
 nsDOMNavigationTiming::NotifyLoadEventStart()
 {
-  if (!mLoadEventStartSet) {
-    mLoadEventStart = DurationFromStart();
-    mLoadEventStartSet = true;
+  if (!mLoadEventStart.IsNull()) {
+    return;
   }
+  mLoadEventStart = TimeStamp::Now();
 }
 
 void
 nsDOMNavigationTiming::NotifyLoadEventEnd()
 {
-  if (!mLoadEventEndSet) {
-    mLoadEventEnd = DurationFromStart();
-    mLoadEventEndSet = true;
+  if (!mLoadEventEnd.IsNull()) {
+    return;
   }
+  mLoadEventEnd = TimeStamp::Now();
 }
 
 void
-nsDOMNavigationTiming::SetDOMLoadingTimeStamp(nsIURI* aURI, mozilla::TimeStamp aValue)
+nsDOMNavigationTiming::SetDOMLoadingTimeStamp(nsIURI* aURI, TimeStamp aValue)
 {
-  if (!mDOMLoadingSet) {
-    mLoadedURI = aURI;
-    mDOMLoading = TimeStampToDOM(aValue);
-    mDOMLoadingSet = true;
+  if (!mDOMLoading.IsNull()) {
+    return;
   }
+  mLoadedURI = aURI;
+  mDOMLoading = aValue;
 }
 
 void
 nsDOMNavigationTiming::NotifyDOMLoading(nsIURI* aURI)
 {
-  if (!mDOMLoadingSet) {
-    mLoadedURI = aURI;
-    mDOMLoading = DurationFromStart();
-    mDOMLoadingSet = true;
+  if (!mDOMLoading.IsNull()) {
+    return;
   }
+  mLoadedURI = aURI;
+  mDOMLoading = TimeStamp::Now();
 }
 
 void
 nsDOMNavigationTiming::NotifyDOMInteractive(nsIURI* aURI)
 {
-  if (!mDOMInteractiveSet) {
-    mLoadedURI = aURI;
-    mDOMInteractive = DurationFromStart();
-    mDOMInteractiveSet = true;
+  if (!mDOMInteractive.IsNull()) {
+    return;
   }
+  mLoadedURI = aURI;
+  mDOMInteractive = TimeStamp::Now();
 }
 
 void
 nsDOMNavigationTiming::NotifyDOMComplete(nsIURI* aURI)
 {
-  if (!mDOMCompleteSet) {
-    mLoadedURI = aURI;
-    mDOMComplete = DurationFromStart();
-    mDOMCompleteSet = true;
+  if (!mDOMComplete.IsNull()) {
+    return;
   }
+  mLoadedURI = aURI;
+  mDOMComplete = TimeStamp::Now();
 }
 
 void
 nsDOMNavigationTiming::NotifyDOMContentLoadedStart(nsIURI* aURI)
 {
-  if (!mDOMContentLoadedEventStartSet) {
-    mLoadedURI = aURI;
-    mDOMContentLoadedEventStart = DurationFromStart();
-    mDOMContentLoadedEventStartSet = true;
+  if (!mDOMContentLoadedEventStart.IsNull()) {
+    return;
   }
+ 
+  mLoadedURI = aURI;
+  mDOMContentLoadedEventStart = TimeStamp::Now();
 }
 
 void
 nsDOMNavigationTiming::NotifyDOMContentLoadedEnd(nsIURI* aURI)
 {
-  if (!mDOMContentLoadedEventEndSet) {
-    mLoadedURI = aURI;
-    mDOMContentLoadedEventEnd = DurationFromStart();
-    mDOMContentLoadedEventEndSet = true;
+  if (!mDOMContentLoadedEventEnd.IsNull()) {
+    return;
   }
+ 
+  mLoadedURI = aURI;
+  mDOMContentLoadedEventEnd = TimeStamp::Now();
 }
 
 void
 nsDOMNavigationTiming::NotifyNonBlankPaintForRootContentDocument()
 {
   MOZ_ASSERT(NS_IsMainThread());
-  MOZ_ASSERT(!mNavigationStartTimeStamp.IsNull());
+  MOZ_ASSERT(!mNavigationStart.IsNull());
 
-  if (!mNonBlankPaintTimeStamp.IsNull()) {
+  if (!mNonBlankPaint.IsNull()) {
     return;
   }
 
-  mNonBlankPaintTimeStamp = TimeStamp::Now();
-  TimeDuration elapsed = mNonBlankPaintTimeStamp - mNavigationStartTimeStamp;
+  mNonBlankPaint = TimeStamp::Now();
+  TimeDuration elapsed = mNonBlankPaint - mNavigationStart;
 
   if (profiler_is_active()) {
     nsAutoCString spec;
@@ -212,8 +206,8 @@ nsDOMNavigationTiming::NotifyNonBlankPaintForRootContentDocument()
 
   if (mDocShellHasBeenActiveSinceNavigationStart) {
     Telemetry::AccumulateTimeDelta(Telemetry::TIME_TO_NON_BLANK_PAINT_MS,
-                                   mNavigationStartTimeStamp,
-                                   mNonBlankPaintTimeStamp);
+                                   mNavigationStart,
+                                   mNonBlankPaint);
   }
 }
 
@@ -224,24 +218,24 @@ nsDOMNavigationTiming::NotifyDocShellStateChanged(DocShellState aDocShellState)
     (aDocShellState == DocShellState::eActive);
 }
 
-DOMTimeMilliSec
-nsDOMNavigationTiming::GetUnloadEventStart()
+mozilla::TimeStamp
+nsDOMNavigationTiming::GetUnloadEventStartTimeStamp() const
 {
   nsIScriptSecurityManager* ssm = nsContentUtils::GetSecurityManager();
   nsresult rv = ssm->CheckSameOriginURI(mLoadedURI, mUnloadedURI, false);
   if (NS_SUCCEEDED(rv)) {
     return mUnloadStart;
   }
-  return 0;
+  return mozilla::TimeStamp();
 }
 
-DOMTimeMilliSec
-nsDOMNavigationTiming::GetUnloadEventEnd()
+mozilla::TimeStamp
+nsDOMNavigationTiming::GetUnloadEventEndTimeStamp() const
 {
   nsIScriptSecurityManager* ssm = nsContentUtils::GetSecurityManager();
   nsresult rv = ssm->CheckSameOriginURI(mLoadedURI, mUnloadedURI, false);
   if (NS_SUCCEEDED(rv)) {
     return mUnloadEnd;
   }
-  return 0;
+  return mozilla::TimeStamp();
 }
diff --git a/dom/base/nsDOMNavigationTiming.h b/dom/base/nsDOMNavigationTiming.h
index 9babece96..3be2527ca 100644
--- a/dom/base/nsDOMNavigationTiming.h
+++ b/dom/base/nsDOMNavigationTiming.h
@@ -47,38 +47,91 @@ public:
 
   mozilla::TimeStamp GetNavigationStartTimeStamp() const
   {
-    return mNavigationStartTimeStamp;
+    return mNavigationStart;
+  }
+
+  DOMTimeMilliSec GetUnloadEventStart()
+  {
+    return TimeStampToDOM(GetUnloadEventStartTimeStamp());
+  }
+
+  DOMTimeMilliSec GetUnloadEventEnd()
+  {
+    return TimeStampToDOM(GetUnloadEventEndTimeStamp());
   }
 
-  DOMTimeMilliSec GetUnloadEventStart();
-  DOMTimeMilliSec GetUnloadEventEnd();
   DOMTimeMilliSec GetDomLoading() const
   {
-    return mDOMLoading;
+    return TimeStampToDOM(mDOMLoading);
   }
   DOMTimeMilliSec GetDomInteractive() const
   {
-    return mDOMInteractive;
+    return TimeStampToDOM(mDOMInteractive);
   }
   DOMTimeMilliSec GetDomContentLoadedEventStart() const
   {
-    return mDOMContentLoadedEventStart;
+    return TimeStampToDOM(mDOMContentLoadedEventStart);
   }
   DOMTimeMilliSec GetDomContentLoadedEventEnd() const
   {
-    return mDOMContentLoadedEventEnd;
+    return TimeStampToDOM(mDOMContentLoadedEventEnd);
   }
   DOMTimeMilliSec GetDomComplete() const
   {
-    return mDOMComplete;
+    return TimeStampToDOM(mDOMComplete);
   }
   DOMTimeMilliSec GetLoadEventStart() const
   {
-    return mLoadEventStart;
+    return TimeStampToDOM(mLoadEventStart);
   }
   DOMTimeMilliSec GetLoadEventEnd() const
   {
-    return mLoadEventEnd;
+    return TimeStampToDOM(mLoadEventEnd);
+  }
+  DOMTimeMilliSec GetTimeToNonBlankPaint() const
+  {
+    return TimeStampToDOM(mNonBlankPaint);
+  }
+
+  DOMHighResTimeStamp GetUnloadEventStartHighRes()
+  {
+    mozilla::TimeStamp stamp = GetUnloadEventStartTimeStamp();
+    if (stamp.IsNull()) {
+      return 0;
+    }
+    return TimeStampToDOMHighRes(stamp);
+  }
+  DOMHighResTimeStamp GetUnloadEventEndHighRes()
+  {
+    mozilla::TimeStamp stamp = GetUnloadEventEndTimeStamp();
+    if (stamp.IsNull()) {
+      return 0;
+    }
+    return TimeStampToDOMHighRes(stamp);
+  }
+  DOMHighResTimeStamp GetDomInteractiveHighRes() const
+  {
+    return TimeStampToDOMHighRes(mDOMInteractive);
+  }
+  DOMHighResTimeStamp GetDomContentLoadedEventStartHighRes() const
+  {
+    return TimeStampToDOMHighRes(mDOMContentLoadedEventStart);
+  }
+  DOMHighResTimeStamp GetDomContentLoadedEventEndHighRes() const
+  {
+    return TimeStampToDOMHighRes(mDOMContentLoadedEventEnd);
+  }
+  DOMHighResTimeStamp GetDomCompleteHighRes() const
+  {
+    return TimeStampToDOMHighRes(mDOMComplete);
+  }
+  DOMHighResTimeStamp GetLoadEventStartHighRes() const
+  {
+    return TimeStampToDOMHighRes(mLoadEventStart);
+  }
+  DOMHighResTimeStamp GetLoadEventEndHighRes() const
+  {
+    return TimeStampToDOMHighRes(mLoadEventEnd);
   }
 
   enum class DocShellState : uint8_t {
@@ -108,9 +161,13 @@ public:
 
   DOMTimeMilliSec TimeStampToDOM(mozilla::TimeStamp aStamp) const;
 
-  inline DOMHighResTimeStamp TimeStampToDOMHighRes(mozilla::TimeStamp aStamp)
+  inline DOMHighResTimeStamp TimeStampToDOMHighRes(mozilla::TimeStamp aStamp) const
   {
-    mozilla::TimeDuration duration = aStamp - mNavigationStartTimeStamp;
+    MOZ_ASSERT(!aStamp.IsNull(), "The timestamp should not be null");
+    if (aStamp.IsNull()) {
+      return 0;
+    }
+    mozilla::TimeDuration duration = aStamp - mNavigationStart;
     return duration.ToMilliseconds();
   }
 
@@ -120,37 +177,29 @@ private:
 
   void Clear();
 
+  mozilla::TimeStamp GetUnloadEventStartTimeStamp() const;
+  mozilla::TimeStamp GetUnloadEventEndTimeStamp() const;
+
   nsCOMPtr<nsIURI> mUnloadedURI;
   nsCOMPtr<nsIURI> mLoadedURI;
 
   Type mNavigationType;
   DOMHighResTimeStamp mNavigationStartHighRes;
-  mozilla::TimeStamp mNavigationStartTimeStamp;
-  mozilla::TimeStamp mNonBlankPaintTimeStamp;
-  DOMTimeMilliSec DurationFromStart();
-
-  DOMTimeMilliSec mBeforeUnloadStart;
-  DOMTimeMilliSec mUnloadStart;
-  DOMTimeMilliSec mUnloadEnd;
-  DOMTimeMilliSec mLoadEventStart;
-  DOMTimeMilliSec mLoadEventEnd;
-
-  DOMTimeMilliSec mDOMLoading;
-  DOMTimeMilliSec mDOMInteractive;
-  DOMTimeMilliSec mDOMContentLoadedEventStart;
-  DOMTimeMilliSec mDOMContentLoadedEventEnd;
-  DOMTimeMilliSec mDOMComplete;
-
-  // Booleans to keep track of what things we've already been notified
-  // about.  We don't update those once we've been notified about them
-  // once.
-  bool mLoadEventStartSet : 1;
-  bool mLoadEventEndSet : 1;
-  bool mDOMLoadingSet : 1;
-  bool mDOMInteractiveSet : 1;
-  bool mDOMContentLoadedEventStartSet : 1;
-  bool mDOMContentLoadedEventEndSet : 1;
-  bool mDOMCompleteSet : 1;
+  mozilla::TimeStamp mNavigationStart;
+  mozilla::TimeStamp mNonBlankPaint;
+
+  mozilla::TimeStamp mBeforeUnloadStart;
+  mozilla::TimeStamp mUnloadStart;
+  mozilla::TimeStamp mUnloadEnd;
+  mozilla::TimeStamp mLoadEventStart;
+  mozilla::TimeStamp mLoadEventEnd;
+
+  mozilla::TimeStamp mDOMLoading;
+  mozilla::TimeStamp mDOMInteractive;
+  mozilla::TimeStamp mDOMContentLoadedEventStart;
+  mozilla::TimeStamp mDOMContentLoadedEventEnd;
+  mozilla::TimeStamp mDOMComplete;
+
   bool mDocShellHasBeenActiveSinceNavigationStart : 1;
 };
 
diff --git a/dom/base/nsDocument.cpp b/dom/base/nsDocument.cpp
index eaea49b02..8acfd901a 100644
--- a/dom/base/nsDocument.cpp
+++ b/dom/base/nsDocument.cpp
@@ -2054,10 +2054,17 @@ nsDocument::ResetToURI(nsIURI *aURI, nsILoadGroup *aLoadGroup,
         mFirstChild = content->GetNextSibling();
       }
       mChildren.RemoveChildAt(i);
+      if (content == mCachedRootElement) {
+        // Immediately clear mCachedRootElement, now that it's been removed
+        // from mChildren, so that GetRootElement() will stop returning this
+        // now-stale value.
+        mCachedRootElement = nullptr;
+      }
       nsNodeUtils::ContentRemoved(this, content, i, previousSibling);
       content->UnbindFromTree();
     }
-    mCachedRootElement = nullptr;
+    MOZ_ASSERT(!mCachedRootElement,
+               "After removing all children, there should be no root elem");
   }
   mInUnlinkOrDeletion = oldVal;
 
@@ -3913,8 +3920,18 @@ nsDocument::RemoveChildAt(uint32_t aIndex, bool aNotify)
     DestroyElementMaps();
   }
 
-  doRemoveChildAt(aIndex, aNotify, oldKid, mChildren);
+  // Preemptively clear mCachedRootElement, since we may be about to remove it
+  // from our child list, and we don't want to return this maybe-obsolete value
+  // from any GetRootElement() calls that happen inside of doRemoveChildAt().
+  // (NOTE: for this to be useful, doRemoveChildAt() must NOT trigger any
+  // GetRootElement() calls until after it's removed the child from mChildren.
+  // Any call before that point would restore this soon-to-be-obsolete cached
+  // answer, and our clearing here would be fruitless.)
   mCachedRootElement = nullptr;
+  doRemoveChildAt(aIndex, aNotify, oldKid, mChildren);
+  MOZ_ASSERT(mCachedRootElement != oldKid,
+             "Stale pointer in mCachedRootElement, after we tried to clear it "
+             "(maybe somebody called GetRootElement() too early?)");
 }
 
 void
@@ -12490,7 +12507,8 @@ nsDocument::ScheduleIntersectionObserverNotification()
 void
 nsDocument::NotifyIntersectionObservers()
 {
-  for (const auto& observer : mIntersectionObservers) {
+  nsTArray<RefPtr<DOMIntersectionObserver>> observers(mIntersectionObservers);
+  for (const auto& observer : observers) {
     observer->Notify();
   }
 }
@@ -12846,3 +12864,19 @@ nsDocument::CheckCustomElementName(const ElementCreationOptions& aOptions,
 
   return is;
 }
+
+Selection*
+nsIDocument::GetSelection(ErrorResult& aRv)
+{
+  nsCOMPtr<nsPIDOMWindowInner> window = GetInnerWindow();
+  if (!window) {
+    return nullptr;
+  }
+
+  NS_ASSERTION(window->IsInnerWindow(), "Should have inner window here!");
+  if (!window->IsCurrentInnerWindow()) {
+    return nullptr;
+  }
+
+  return nsGlobalWindow::Cast(window)->GetSelection(aRv);
+}
diff --git a/dom/base/nsFrameMessageManager.cpp b/dom/base/nsFrameMessageManager.cpp
index 049bc0a1a..6fffd376b 100644
--- a/dom/base/nsFrameMessageManager.cpp
+++ b/dom/base/nsFrameMessageManager.cpp
@@ -271,10 +271,10 @@ BuildClonedMessageData(typename BlobTraits<Flavor>::ConcreteContentManagerType*
                        ClonedMessageData& aClonedData)
 {
   SerializedStructuredCloneBuffer& buffer = aClonedData.data();
-  auto iter = aData.Data().Iter();
+  auto iter = aData.Data().Start();
   size_t size = aData.Data().Size();
   bool success;
-  buffer.data = aData.Data().Borrow<js::SystemAllocPolicy>(iter, size, &success);
+  buffer.data = aData.Data().Borrow(iter, size, &success);
   if (NS_WARN_IF(!success)) {
     return false;
   }
@@ -1286,6 +1286,7 @@ nsFrameMessageManager::ReceiveMessage(nsISupports* aTarget,
         if (aRetVal) {
           ErrorResult rv;
           StructuredCloneData* data = aRetVal->AppendElement();
+          data->InitScope(JS::StructuredCloneScope::DifferentProcess);
           data->Write(cx, rval, rv);
           if (NS_WARN_IF(rv.Failed())) {
             aRetVal->RemoveElementAt(aRetVal->Length() - 1);
diff --git a/dom/base/nsGkAtomList.h b/dom/base/nsGkAtomList.h
index e4ae7ede8..8fefa0e02 100644
--- a/dom/base/nsGkAtomList.h
+++ b/dom/base/nsGkAtomList.h
@@ -694,6 +694,7 @@ GK_ATOM(onadapterremoved, "onadapterremoved")
 GK_ATOM(onafterprint, "onafterprint")
 GK_ATOM(onafterscriptexecute, "onafterscriptexecute")
 GK_ATOM(onalerting, "onalerting")
+GK_ATOM(onanimationcancel, "onanimationcancel")
 GK_ATOM(onanimationend, "onanimationend")
 GK_ATOM(onanimationiteration, "onanimationiteration")
 GK_ATOM(onanimationstart, "onanimationstart")
@@ -704,6 +705,7 @@ GK_ATOM(onattributechanged, "onattributechanged")
 GK_ATOM(onattributereadreq, "onattributereadreq")
 GK_ATOM(onattributewritereq, "onattributewritereq")
 GK_ATOM(onaudioprocess, "onaudioprocess")
+GK_ATOM(onauxclick, "onauxclick")
 GK_ATOM(onbeforecopy, "onbeforecopy")
 GK_ATOM(onbeforecut, "onbeforecut")
 GK_ATOM(onbeforepaste, "onbeforepaste")
@@ -941,6 +943,7 @@ GK_ATOM(ontouchstart, "ontouchstart")
 GK_ATOM(ontouchend, "ontouchend")
 GK_ATOM(ontouchmove, "ontouchmove")
 GK_ATOM(ontouchcancel, "ontouchcancel")
+GK_ATOM(ontransitioncancel, "ontransitioncancel")
 GK_ATOM(ontransitionend, "ontransitionend")
 GK_ATOM(ontransitionrun, "ontransitionrun")
 GK_ATOM(ontransitionstart, "ontransitionstart")
@@ -2237,6 +2240,7 @@ GK_ATOM(windows_accent_color_applies, "windows-accent-color-applies")
 GK_ATOM(windows_accent_color_is_dark, "windows-accent-color-is-dark")
 GK_ATOM(windows_default_theme, "windows-default-theme")
 GK_ATOM(mac_graphite_theme, "mac-graphite-theme")
+GK_ATOM(mac_lion_theme, "mac-lion-theme")
 GK_ATOM(mac_yosemite_theme, "mac-yosemite-theme")
 GK_ATOM(windows_compositor, "windows-compositor")
 GK_ATOM(windows_glass, "windows-glass")
@@ -2268,6 +2272,7 @@ GK_ATOM(_moz_windows_accent_color_applies, "-moz-windows-accent-color-applies")
 GK_ATOM(_moz_windows_accent_color_is_dark, "-moz-windows-accent-color-is-dark")
 GK_ATOM(_moz_windows_default_theme, "-moz-windows-default-theme")
 GK_ATOM(_moz_mac_graphite_theme, "-moz-mac-graphite-theme")
+GK_ATOM(_moz_mac_lion_theme, "-moz-mac-lion-theme")
 GK_ATOM(_moz_mac_yosemite_theme, "-moz-mac-yosemite-theme")
 GK_ATOM(_moz_windows_compositor, "-moz-windows-compositor")
 GK_ATOM(_moz_windows_classic, "-moz-windows-classic")
diff --git a/dom/base/nsGlobalWindow.cpp b/dom/base/nsGlobalWindow.cpp
index f784031f6..884ad69ca 100644
--- a/dom/base/nsGlobalWindow.cpp
+++ b/dom/base/nsGlobalWindow.cpp
@@ -23,8 +23,9 @@
 #include "mozilla/dom/StorageEvent.h"
 #include "mozilla/dom/StorageEventBinding.h"
 #include "mozilla/dom/Timeout.h"
+#include "mozilla/dom/TimeoutHandler.h"
 #include "mozilla/IntegerPrintfMacros.h"
-#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
+#if defined(MOZ_WIDGET_ANDROID)
 #include "mozilla/dom/WindowOrientationObserver.h"
 #endif
 #include "nsDOMOfflineResourceList.h"
@@ -248,10 +249,6 @@
 #include "mozilla/dom/SpeechSynthesis.h"
 #endif
 
-#ifdef MOZ_B2G
-#include "nsPISocketTransportService.h"
-#endif
-
 // Apple system headers seem to have a check() macro.  <sigh>
 #ifdef check
 class nsIScriptTimeoutHandler;
@@ -552,29 +549,284 @@ DialogValueHolder::Get(JSContext* aCx, JS::Handle<JSObject*> aScope,
   }
 }
 
+class IdleRequestExecutor final : public nsIRunnable
+                                , public nsICancelableRunnable
+                                , public nsIIncrementalRunnable
+{
+public:
+  explicit IdleRequestExecutor(nsGlobalWindow* aWindow)
+    : mDispatched(false)
+    , mDeadline(TimeStamp::Now())
+    , mWindow(aWindow)
+  {
+    MOZ_DIAGNOSTIC_ASSERT(mWindow);
+    MOZ_DIAGNOSTIC_ASSERT(mWindow->IsInnerWindow());
+  }
+
+  NS_DECL_CYCLE_COLLECTING_ISUPPORTS
+  NS_DECL_CYCLE_COLLECTION_CLASS_AMBIGUOUS(IdleRequestExecutor, nsIRunnable)
+
+  NS_DECL_NSIRUNNABLE
+  nsresult Cancel() override;
+  void SetDeadline(TimeStamp aDeadline) override;
+
+  void MaybeDispatch();
+private:
+  ~IdleRequestExecutor() {}
+
+  bool mDispatched;
+  TimeStamp mDeadline;
+  RefPtr<nsGlobalWindow> mWindow;
+};
+
+NS_IMPL_CYCLE_COLLECTION_CLASS(IdleRequestExecutor)
+
+NS_IMPL_CYCLE_COLLECTING_ADDREF(IdleRequestExecutor)
+NS_IMPL_CYCLE_COLLECTING_RELEASE(IdleRequestExecutor)
+
+NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(IdleRequestExecutor)
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mWindow)
+NS_IMPL_CYCLE_COLLECTION_UNLINK_END
+
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN(IdleRequestExecutor)
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mWindow)
+NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(IdleRequestExecutor)
+  NS_INTERFACE_MAP_ENTRY(nsIRunnable)
+  NS_INTERFACE_MAP_ENTRY(nsICancelableRunnable)
+  NS_INTERFACE_MAP_ENTRY(nsIIncrementalRunnable)
+  NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIRunnable)
+NS_INTERFACE_MAP_END
+
+NS_IMETHODIMP
+IdleRequestExecutor::Run()
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  mDispatched = false;
+  if (mWindow) {
+    return mWindow->ExecuteIdleRequest(mDeadline);
+  }
+
+  return NS_OK;
+}
+
+nsresult
+IdleRequestExecutor::Cancel()
+{
+  MOZ_ASSERT(NS_IsMainThread());
+
+  mWindow = nullptr;
+  return NS_OK;
+}
+
 void
-nsGlobalWindow::PostThrottledIdleCallback()
+IdleRequestExecutor::SetDeadline(TimeStamp aDeadline)
 {
-  AssertIsOnMainThread();
+  MOZ_ASSERT(NS_IsMainThread());
+
+  if (!mWindow) {
+    return;
+  }
 
-  if (mThrottledIdleRequestCallbacks.isEmpty())
+  mDeadline = aDeadline;
+}
+
+void
+IdleRequestExecutor::MaybeDispatch()
+{
+  // If we've already dispatched the executor we don't want to do it
+  // again. Also, if we've called IdleRequestExecutor::Cancel mWindow
+  // will be null, which indicates that we shouldn't dispatch this
+  // executor either.
+  if (mDispatched || !mWindow) {
     return;
+  }
 
-  RefPtr<IdleRequest> request(mThrottledIdleRequestCallbacks.popFirst());
-  // ownership transferred from mThrottledIdleRequestCallbacks to
-  // mIdleRequestCallbacks
-  mIdleRequestCallbacks.insertBack(request);
+  mDispatched = true;
+  RefPtr<IdleRequestExecutor> request = this;
   NS_IdleDispatchToCurrentThread(request.forget());
 }
 
-/* static */ void
-nsGlobalWindow::InsertIdleCallbackIntoList(IdleRequest* aRequest,
-                                           IdleRequests& aList)
+class IdleRequestExecutorTimeoutHandler final : public TimeoutHandler
 {
-  aList.insertBack(aRequest);
+public:
+  explicit IdleRequestExecutorTimeoutHandler(IdleRequestExecutor* aExecutor)
+    : mExecutor(aExecutor)
+  {
+  }
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(IdleRequestExecutorTimeoutHandler,
+                                           TimeoutHandler)
+
+  nsresult Call() override
+  {
+    mExecutor->MaybeDispatch();
+    return NS_OK;
+  }
+private:
+  ~IdleRequestExecutorTimeoutHandler() {}
+  RefPtr<IdleRequestExecutor> mExecutor;
+};
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(IdleRequestExecutorTimeoutHandler, TimeoutHandler, mExecutor)
+
+NS_IMPL_ADDREF_INHERITED(IdleRequestExecutorTimeoutHandler, TimeoutHandler)
+NS_IMPL_RELEASE_INHERITED(IdleRequestExecutorTimeoutHandler, TimeoutHandler)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(IdleRequestExecutorTimeoutHandler)
+  NS_INTERFACE_MAP_ENTRY(nsITimeoutHandler)
+NS_INTERFACE_MAP_END_INHERITING(TimeoutHandler)
+
+void
+nsGlobalWindow::ScheduleIdleRequestDispatch()
+{
+  AssertIsOnMainThread();
+
+  if (mIdleRequestCallbacks.isEmpty()) {
+    if (mIdleRequestExecutor) {
+      mIdleRequestExecutor->Cancel();
+      mIdleRequestExecutor = nullptr;
+    }
+
+    return;
+  }
+
+  if (!mIdleRequestExecutor) {
+    mIdleRequestExecutor = new IdleRequestExecutor(this);
+  }
+
+  nsPIDOMWindowOuter* outer = GetOuterWindow();
+  if (outer && outer->AsOuter()->IsBackground()) {
+    nsCOMPtr<nsITimeoutHandler> handler = new IdleRequestExecutorTimeoutHandler(mIdleRequestExecutor);
+    int32_t dummy;
+    // Set a timeout handler with a timeout of 0 ms to throttle idle
+    // callback requests coming from a backround window using
+    // background timeout throttling.
+    SetTimeoutOrInterval(handler, 0, false,
+                         Timeout::Reason::eIdleCallbackTimeout, &dummy);
+    return;
+  }
+
+  mIdleRequestExecutor->MaybeDispatch();
+}
+
+void
+nsGlobalWindow::SuspendIdleRequests()
+{
+  if (mIdleRequestExecutor) {
+    mIdleRequestExecutor->Cancel();
+    mIdleRequestExecutor = nullptr;
+  }
+}
+
+void
+nsGlobalWindow::ResumeIdleRequests()
+{
+  MOZ_ASSERT(!mIdleRequestExecutor);
+
+  ScheduleIdleRequestDispatch();
+}
+
+void
+nsGlobalWindow::InsertIdleCallback(IdleRequest* aRequest)
+{
+  AssertIsOnMainThread();
+  mIdleRequestCallbacks.insertBack(aRequest);
   aRequest->AddRef();
 }
 
+void
+nsGlobalWindow::RemoveIdleCallback(mozilla::dom::IdleRequest* aRequest)
+{
+  AssertIsOnMainThread();
+
+  if (aRequest->HasTimeout()) {
+    ClearTimeoutOrInterval(aRequest->GetTimeoutHandle(),
+                           Timeout::Reason::eIdleCallbackTimeout);
+  }
+
+  aRequest->removeFrom(mIdleRequestCallbacks);
+  aRequest->Release();
+}
+
+nsresult
+nsGlobalWindow::RunIdleRequest(IdleRequest* aRequest,
+                               DOMHighResTimeStamp aDeadline,
+                               bool aDidTimeout)
+{
+  AssertIsOnMainThread();
+  RefPtr<IdleRequest> request(aRequest);
+  RemoveIdleCallback(request);
+  return request->IdleRun(AsInner(), aDeadline, aDidTimeout);
+}
+
+nsresult
+nsGlobalWindow::ExecuteIdleRequest(TimeStamp aDeadline)
+{
+  AssertIsOnMainThread();
+  RefPtr<IdleRequest> request = mIdleRequestCallbacks.getFirst();
+
+  if (!request) {
+    // There are no more idle requests, so stop scheduling idle
+    // request callbacks.
+    return NS_OK;
+  }
+
+  DOMHighResTimeStamp deadline = 0.0;
+
+  if (Performance* perf = GetPerformance()) {
+    deadline = perf->GetDOMTiming()->TimeStampToDOMHighRes(aDeadline);
+  }
+
+  nsresult result = RunIdleRequest(request, deadline, false);
+
+  ScheduleIdleRequestDispatch();
+  return result;
+}
+
+class IdleRequestTimeoutHandler final : public TimeoutHandler
+{
+public:
+  IdleRequestTimeoutHandler(JSContext* aCx,
+                            IdleRequest* aIdleRequest,
+                            nsPIDOMWindowInner* aWindow)
+    : TimeoutHandler(aCx)
+    , mIdleRequest(aIdleRequest)
+    , mWindow(aWindow)
+  {
+  }
+
+  NS_DECL_ISUPPORTS_INHERITED
+  NS_DECL_CYCLE_COLLECTION_CLASS_INHERITED(IdleRequestTimeoutHandler,
+                                           TimeoutHandler)
+
+  nsresult Call() override
+  {
+    return nsGlobalWindow::Cast(mWindow)->RunIdleRequest(mIdleRequest, 0.0, true);
+  }
+
+private:
+  ~IdleRequestTimeoutHandler() {}
+
+  RefPtr<IdleRequest> mIdleRequest;
+  nsCOMPtr<nsPIDOMWindowInner> mWindow;
+};
+
+NS_IMPL_CYCLE_COLLECTION_INHERITED(IdleRequestTimeoutHandler,
+                                   TimeoutHandler,
+                                   mIdleRequest,
+                                   mWindow)
+
+NS_IMPL_ADDREF_INHERITED(IdleRequestTimeoutHandler, TimeoutHandler)
+NS_IMPL_RELEASE_INHERITED(IdleRequestTimeoutHandler, TimeoutHandler)
+
+NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(IdleRequestTimeoutHandler)
+  NS_INTERFACE_MAP_ENTRY(nsITimeoutHandler)
+NS_INTERFACE_MAP_END_INHERITING(TimeoutHandler)
+
 uint32_t
 nsGlobalWindow::RequestIdleCallback(JSContext* aCx,
                                     IdleRequestCallback& aCallback,
@@ -584,33 +836,36 @@ nsGlobalWindow::RequestIdleCallback(JSContext* aCx,
   MOZ_RELEASE_ASSERT(IsInnerWindow());
   AssertIsOnMainThread();
 
-  uint32_t handle = ++mIdleRequestCallbackCounter;
+  uint32_t handle = mIdleRequestCallbackCounter++;
 
   RefPtr<IdleRequest> request =
-    new IdleRequest(aCx, AsInner(), aCallback, handle);
+    new IdleRequest(&aCallback, handle);
 
   if (aOptions.mTimeout.WasPassed()) {
-    aError = request->SetTimeout(aOptions.mTimeout.Value());
-    if (NS_WARN_IF(aError.Failed())) {
+    int32_t timeoutHandle;
+    nsCOMPtr<nsITimeoutHandler> handler(new IdleRequestTimeoutHandler(aCx, request, AsInner()));
+
+    nsresult rv = SetTimeoutOrInterval(
+        handler, aOptions.mTimeout.Value(), false,
+        Timeout::Reason::eIdleCallbackTimeout, &timeoutHandle);
+
+    if (NS_WARN_IF(NS_FAILED(rv))) {
       return 0;
     }
-  }
 
-  nsGlobalWindow* outer = GetOuterWindowInternal();
-  if (outer && outer->AsOuter()->IsBackground()) {
-    // mThrottledIdleRequestCallbacks now owns request
-    InsertIdleCallbackIntoList(request, mThrottledIdleRequestCallbacks);
-
-    NS_DelayedDispatchToCurrentThread(
-      NewRunnableMethod(this, &nsGlobalWindow::PostThrottledIdleCallback),
-      10000);
-  } else {
-    MOZ_ASSERT(mThrottledIdleRequestCallbacks.isEmpty());
+    request->SetTimeoutHandle(timeoutHandle);
+  }
 
-    // mIdleRequestCallbacks now owns request
-    InsertIdleCallbackIntoList(request, mIdleRequestCallbacks);
+  // If the list of idle callback requests is not empty it means that
+  // we've already dispatched the first idle request. If we're
+  // suspended we should only queue the idle callback and not schedule
+  // it to run, that will be done in ResumeIdleRequest.
+  bool needsScheduling = !IsSuspended() && mIdleRequestCallbacks.isEmpty();
+  // mIdleRequestCallbacks now owns request
+  InsertIdleCallback(request);
 
-    NS_IdleDispatchToCurrentThread(request.forget());
+  if (needsScheduling) {
+    ScheduleIdleRequestDispatch();
   }
 
   return handle;
@@ -623,7 +878,7 @@ nsGlobalWindow::CancelIdleCallback(uint32_t aHandle)
 
   for (IdleRequest* r : mIdleRequestCallbacks) {
     if (r->Handle() == aHandle) {
-      r->Cancel();
+      RemoveIdleCallback(r);
       break;
     }
   }
@@ -632,29 +887,17 @@ nsGlobalWindow::CancelIdleCallback(uint32_t aHandle)
 void
 nsGlobalWindow::DisableIdleCallbackRequests()
 {
-  while (!mIdleRequestCallbacks.isEmpty()) {
-    RefPtr<IdleRequest> request = mIdleRequestCallbacks.popFirst();
-    request->Cancel();
+  if (mIdleRequestExecutor) {
+    mIdleRequestExecutor->Cancel();
+    mIdleRequestExecutor = nullptr;
   }
 
-  while (!mThrottledIdleRequestCallbacks.isEmpty()) {
-    RefPtr<IdleRequest> request = mThrottledIdleRequestCallbacks.popFirst();
-    request->Cancel();
-  }
-}
-
-void nsGlobalWindow::UnthrottleIdleCallbackRequests()
-{
-  AssertIsOnMainThread();
-
-  while (!mThrottledIdleRequestCallbacks.isEmpty()) {
-    RefPtr<IdleRequest> request(mThrottledIdleRequestCallbacks.popFirst());
-    mIdleRequestCallbacks.insertBack(request);
-    NS_IdleDispatchToCurrentThread(request.forget());
+  while (!mIdleRequestCallbacks.isEmpty()) {
+    RefPtr<IdleRequest> request = mIdleRequestCallbacks.getFirst();
+    RemoveIdleCallback(request);
   }
 }
 
-
 namespace mozilla {
 namespace dom {
 extern uint64_t
@@ -1306,13 +1549,10 @@ nsGlobalWindow::nsGlobalWindow(nsGlobalWindow *aOuterWindow)
     mSerial(0),
     mIdleCallbackTimeoutCounter(1),
     mIdleRequestCallbackCounter(1),
+    mIdleRequestExecutor(nullptr),
 #ifdef DEBUG
     mSetOpenerWindowCalled(false),
 #endif
-#ifdef MOZ_B2G
-    mNetworkUploadObserverEnabled(false),
-    mNetworkDownloadObserverEnabled(false),
-#endif
     mCleanedUp(false),
     mDialogAbuseCount(0),
     mAreDialogsEnabled(true),
@@ -1665,11 +1905,6 @@ nsGlobalWindow::CleanUp()
       os->RemoveObserver(mObserver, "dom-storage2-changed");
     }
 
-#ifdef MOZ_B2G
-    DisableNetworkEvent(eNetworkUpload);
-    DisableNetworkEvent(eNetworkDownload);
-#endif // MOZ_B2G
-
     if (mIdleService) {
       mIdleService->RemoveIdleObserver(mObserver, MIN_IDLE_NOTIFICATION_TIME_S);
     }
@@ -1713,7 +1948,7 @@ nsGlobalWindow::CleanUp()
   mSpeechSynthesis = nullptr;
 #endif
 
-#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
+#if defined(MOZ_WIDGET_ANDROID)
   mOrientationChangeObserver = nullptr;
 #endif
 
@@ -1738,9 +1973,6 @@ nsGlobalWindow::CleanUp()
     mHasGamepad = false;
     DisableVRUpdates();
     mHasVREvents = false;
-#ifdef MOZ_B2G
-    DisableTimeChangeNotifications();
-#endif
     DisableIdleCallbackRequests();
   } else {
     MOZ_ASSERT(!mHasGamepad);
@@ -1844,7 +2076,7 @@ nsGlobalWindow::FreeInnerObjects()
     mScreen = nullptr;
   }
 
-#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
+#if defined(MOZ_WIDGET_ANDROID)
   mOrientationChangeObserver = nullptr;
 #endif
 
@@ -2033,14 +2265,11 @@ NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INTERNAL(nsGlobalWindow)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mWakeLock)
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mPendingStorageEvents)
 
+  NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mIdleRequestExecutor)
   for (IdleRequest* request : tmp->mIdleRequestCallbacks) {
     cb.NoteNativeChild(request, NS_CYCLE_COLLECTION_PARTICIPANT(IdleRequest));
   }
 
-  for (IdleRequest* request : tmp->mThrottledIdleRequestCallbacks) {
-    cb.NoteNativeChild(request, NS_CYCLE_COLLECTION_PARTICIPANT(IdleRequest));
-  }
-
   NS_IMPL_CYCLE_COLLECTION_TRAVERSE(mIdleObservers)
 
 #ifdef MOZ_GAMEPAD
@@ -2147,6 +2376,7 @@ NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN(nsGlobalWindow)
 
   tmp->UnlinkHostObjectURIs();
 
+  NS_IMPL_CYCLE_COLLECTION_UNLINK(mIdleRequestExecutor)
   tmp->DisableIdleCallbackRequests();
 
   NS_IMPL_CYCLE_COLLECTION_UNLINK_PRESERVED_WRAPPER
@@ -2275,8 +2505,13 @@ nsGlobalWindow::WouldReuseInnerWindow(nsIDocument* aNewDocument)
     return false;
   }
 
-  NS_ASSERTION(NS_IsAboutBlank(mDoc->GetDocumentURI()),
-               "How'd this happen?");
+#ifdef DEBUG
+{
+  nsCOMPtr<nsIURI> uri;
+  mDoc->GetDocumentURI()->CloneIgnoringRef(getter_AddRefs(uri));
+  NS_ASSERTION(NS_IsAboutBlank(uri), "How'd this happen?");
+}
+#endif
 
   // Great, we're the original document, check for one of the other
   // conditions.
@@ -2878,8 +3113,7 @@ nsGlobalWindow::SetNewDocument(nsIDocument* aDocument,
           newInnerWindow->mPerformance =
             Performance::CreateForMainThread(newInnerWindow->AsInner(),
                                              currentInner->mPerformance->GetDOMTiming(),
-                                             currentInner->mPerformance->GetChannel(),
-                                             currentInner->mPerformance->GetParentPerformance());
+                                             currentInner->mPerformance->GetChannel());
         }
       }
 
@@ -4093,22 +4327,7 @@ nsPIDOMWindowInner::CreatePerformanceObjectIfNeeded()
     timedChannel = nullptr;
   }
   if (timing) {
-    // If we are dealing with an iframe, we will need the parent's performance
-    // object (so we can add the iframe as a resource of that page).
-    Performance* parentPerformance = nullptr;
-    nsCOMPtr<nsPIDOMWindowOuter> parentWindow = GetScriptableParentOrNull();
-    if (parentWindow) {
-      nsPIDOMWindowInner* parentInnerWindow = nullptr;
-      if (parentWindow) {
-        parentInnerWindow = parentWindow->GetCurrentInnerWindow();
-      }
-      if (parentInnerWindow) {
-        parentPerformance = parentInnerWindow->GetPerformance();
-      }
-    }
-    mPerformance =
-      Performance::CreateForMainThread(this, timing, timedChannel,
-                                       parentPerformance);
+    mPerformance = Performance::CreateForMainThread(this, timing, timedChannel);
   }
 }
 
@@ -10237,12 +10456,6 @@ void nsGlobalWindow::SetIsBackground(bool aIsBackground)
     ResetTimersForThrottleReduction(gMinBackgroundTimeoutValue);
   }
 
-  if (!aIsBackground) {
-    nsGlobalWindow* inner = GetCurrentInnerWindowInternal();
-    if (inner) {
-      inner->UnthrottleIdleCallbackRequests();
-    }
-  }
 #ifdef MOZ_GAMEPAD
   if (!aIsBackground) {
     nsGlobalWindow* inner = GetCurrentInnerWindowInternal();
@@ -11904,27 +12117,6 @@ nsGlobalWindow::Observe(nsISupports* aSubject, const char* aTopic,
     return NS_OK;
   }
 
-#ifdef MOZ_B2G
-  if (!nsCRT::strcmp(aTopic, NS_NETWORK_ACTIVITY_BLIP_UPLOAD_TOPIC) ||
-      !nsCRT::strcmp(aTopic, NS_NETWORK_ACTIVITY_BLIP_DOWNLOAD_TOPIC)) {
-    MOZ_ASSERT(IsInnerWindow());
-    if (!AsInner()->IsCurrentInnerWindow()) {
-      return NS_OK;
-    }
-
-    RefPtr<Event> event = NS_NewDOMEvent(this, nullptr, nullptr);
-    event->InitEvent(
-      !nsCRT::strcmp(aTopic, NS_NETWORK_ACTIVITY_BLIP_UPLOAD_TOPIC)
-        ? NETWORK_UPLOAD_EVENT_NAME
-        : NETWORK_DOWNLOAD_EVENT_NAME,
-      false, false);
-    event->SetTrusted(true);
-
-    bool dummy;
-    return DispatchEvent(event, &dummy);
-  }
-#endif // MOZ_B2G
-
   if (!nsCRT::strcmp(aTopic, NS_PREFBRANCH_PREFCHANGE_TOPIC_ID)) {
     MOZ_ASSERT(!NS_strcmp(aData, u"intl.accept_languages"));
     MOZ_ASSERT(IsInnerWindow());
@@ -12036,6 +12228,8 @@ nsGlobalWindow::Suspend()
 
   mozilla::dom::workers::SuspendWorkersForWindow(AsInner());
 
+  SuspendIdleRequests();
+
   for (Timeout* t = mTimeouts.getFirst(); t; t = t->getNext()) {
     // Leave the timers with the current time remaining.  This will
     // cause the timers to potentially fire when the window is
@@ -12146,6 +12340,8 @@ nsGlobalWindow::Resume()
     t->AddRef();
   }
 
+  ResumeIdleRequests();
+
   // Resume all of the workers for this window.  We must do this
   // after timeouts since workers may have queued events that can trigger
   // a setTimeout().
@@ -13813,7 +14009,7 @@ nsGlobalWindow::DisableDeviceSensor(uint32_t aType)
   }
 }
 
-#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
+#if defined(MOZ_WIDGET_ANDROID)
 void
 nsGlobalWindow::EnableOrientationChangeListener()
 {
@@ -14437,7 +14633,9 @@ nsGlobalWindow::NotifyDefaultButtonLoaded(Element& aDefaultButton,
     return;
   }
   LayoutDeviceIntRect buttonRect =
-    LayoutDeviceIntRect::FromUnknownRect(frame->GetScreenRect());
+    LayoutDeviceIntRect::FromAppUnitsToNearest(
+      frame->GetScreenRectInAppUnits(),
+      frame->PresContext()->AppUnitsPerDevPixel());
 
   // Get the widget rect in screen coordinates.
   nsIWidget *widget = GetNearestWidget();
@@ -14706,7 +14904,7 @@ nsGlobalWindow::IsModalContentWindow(JSContext* aCx, JSObject* aGlobal)
   return xpc::WindowOrNull(aGlobal)->IsModalContentWindow();
 }
 
-#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
+#if defined(MOZ_WIDGET_ANDROID)
 int16_t
 nsGlobalWindow::Orientation(CallerType aCallerType) const
 {
@@ -14820,80 +15018,6 @@ nsGlobalWindow::GetIsPrerendered()
   return docShell && docShell->GetIsPrerendered();
 }
 
-#ifdef MOZ_B2G
-void
-nsGlobalWindow::EnableNetworkEvent(EventMessage aEventMessage)
-{
-  MOZ_ASSERT(IsInnerWindow());
-
-  nsCOMPtr<nsIPermissionManager> permMgr =
-    services::GetPermissionManager();
-  if (!permMgr) {
-    NS_ERROR("No PermissionManager available!");
-    return;
-  }
-
-  uint32_t permission = nsIPermissionManager::DENY_ACTION;
-  permMgr->TestExactPermissionFromPrincipal(GetPrincipal(), "network-events",
-                                            &permission);
-
-  if (permission != nsIPermissionManager::ALLOW_ACTION) {
-    return;
-  }
-
-  nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
-  if (!os) {
-    NS_ERROR("ObserverService should be available!");
-    return;
-  }
-
-  switch (aEventMessage) {
-    case eNetworkUpload:
-      if (!mNetworkUploadObserverEnabled) {
-        mNetworkUploadObserverEnabled = true;
-        os->AddObserver(mObserver, NS_NETWORK_ACTIVITY_BLIP_UPLOAD_TOPIC, false);
-      }
-      break;
-    case eNetworkDownload:
-      if (!mNetworkDownloadObserverEnabled) {
-        mNetworkDownloadObserverEnabled = true;
-        os->AddObserver(mObserver, NS_NETWORK_ACTIVITY_BLIP_DOWNLOAD_TOPIC, false);
-      }
-      break;
-    default:
-      break;
-  }
-}
-
-void
-nsGlobalWindow::DisableNetworkEvent(EventMessage aEventMessage)
-{
-  MOZ_ASSERT(IsInnerWindow());
-
-  nsCOMPtr<nsIObserverService> os = mozilla::services::GetObserverService();
-  if (!os) {
-    return;
-  }
-
-  switch (aEventMessage) {
-    case eNetworkUpload:
-      if (mNetworkUploadObserverEnabled) {
-        mNetworkUploadObserverEnabled = false;
-        os->RemoveObserver(mObserver, NS_NETWORK_ACTIVITY_BLIP_UPLOAD_TOPIC);
-      }
-      break;
-    case eNetworkDownload:
-      if (mNetworkDownloadObserverEnabled) {
-        mNetworkDownloadObserverEnabled = false;
-        os->RemoveObserver(mObserver, NS_NETWORK_ACTIVITY_BLIP_DOWNLOAD_TOPIC);
-      }
-      break;
-    default:
-      break;
-  }
-}
-#endif // MOZ_B2G
-
 void
 nsGlobalWindow::RedefineProperty(JSContext* aCx, const char* aPropName,
                                  JS::Handle<JS::Value> aValue,
diff --git a/dom/base/nsGlobalWindow.h b/dom/base/nsGlobalWindow.h
index dbceeab74..467bc6796 100644
--- a/dom/base/nsGlobalWindow.h
+++ b/dom/base/nsGlobalWindow.h
@@ -102,6 +102,8 @@ struct nsRect;
 
 class nsWindowSizes;
 
+class IdleRequestExecutor;
+
 namespace mozilla {
 class DOMEventTargetHelper;
 class ThrottledEventQueue;
@@ -118,6 +120,7 @@ class Gamepad;
 enum class ImageBitmapFormat : uint32_t;
 class IdleRequest;
 class IdleRequestCallback;
+class IncrementalRunnable;
 class Location;
 class MediaQueryList;
 class MozSelfSupport;
@@ -135,7 +138,7 @@ class U2F;
 class VRDisplay;
 class VREventObserver;
 class WakeLock;
-#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
+#if defined(MOZ_WIDGET_ANDROID)
 class WindowOrientationObserver;
 #endif
 class Worklet;
@@ -628,7 +631,7 @@ public:
   virtual void EnableDeviceSensor(uint32_t aType) override;
   virtual void DisableDeviceSensor(uint32_t aType) override;
 
-#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
+#if defined(MOZ_WIDGET_ANDROID)
   virtual void EnableOrientationChangeListener() override;
   virtual void DisableOrientationChangeListener() override;
 #endif
@@ -636,13 +639,6 @@ public:
   virtual void EnableTimeChangeNotifications() override;
   virtual void DisableTimeChangeNotifications() override;
 
-#ifdef MOZ_B2G
-  // Inner windows only.
-  virtual void EnableNetworkEvent(mozilla::EventMessage aEventMessage) override;
-  virtual void DisableNetworkEvent(
-                 mozilla::EventMessage aEventMessage) override;
-#endif // MOZ_B2G
-
   virtual nsresult SetArguments(nsIArray* aArguments) override;
 
   void MaybeForgiveSpamCount();
@@ -909,7 +905,7 @@ public:
   nsIDOMOfflineResourceList* GetApplicationCache(mozilla::ErrorResult& aError);
   already_AddRefed<nsIDOMOfflineResourceList> GetApplicationCache() override;
 
-#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
+#if defined(MOZ_WIDGET_ANDROID)
   int16_t Orientation(mozilla::dom::CallerType aCallerType) const;
 #endif
 
@@ -1097,7 +1093,6 @@ public:
                                mozilla::ErrorResult& aError);
   void CancelIdleCallback(uint32_t aHandle);
 
-
 #ifdef MOZ_WEBSPEECH
   mozilla::dom::SpeechSynthesis*
     GetSpeechSynthesis(mozilla::ErrorResult& aError);
@@ -1762,6 +1757,21 @@ private:
   mozilla::dom::TabGroup* TabGroupInner();
   mozilla::dom::TabGroup* TabGroupOuter();
 
+public:
+  void DisableIdleCallbackRequests();
+  uint32_t IdleRequestHandle() const { return mIdleRequestCallbackCounter; }
+  nsresult RunIdleRequest(mozilla::dom::IdleRequest* aRequest,
+                          DOMHighResTimeStamp aDeadline, bool aDidTimeout);
+  nsresult ExecuteIdleRequest(TimeStamp aDeadline);
+  void ScheduleIdleRequestDispatch();
+  void SuspendIdleRequests();
+  void ResumeIdleRequests();
+
+  typedef mozilla::LinkedList<mozilla::dom::IdleRequest> IdleRequests;
+  void InsertIdleCallback(mozilla::dom::IdleRequest* aRequest);
+
+  void RemoveIdleCallback(mozilla::dom::IdleRequest* aRequest);
+
 protected:
   // These members are only used on outer window objects. Make sure
   // you never set any of these on an inner object!
@@ -1912,32 +1922,18 @@ protected:
 
   uint32_t mSerial;
 
-  void DisableIdleCallbackRequests();
-  void UnthrottleIdleCallbackRequests();
-
-  void PostThrottledIdleCallback();
-
-  typedef mozilla::LinkedList<mozilla::dom::IdleRequest> IdleRequests;
-  static void InsertIdleCallbackIntoList(mozilla::dom::IdleRequest* aRequest,
-                                         IdleRequests& aList);
-
    // The current idle request callback timeout handle
   uint32_t mIdleCallbackTimeoutCounter;
   // The current idle request callback handle
   uint32_t mIdleRequestCallbackCounter;
   IdleRequests mIdleRequestCallbacks;
-  IdleRequests mThrottledIdleRequestCallbacks;
+  RefPtr<IdleRequestExecutor> mIdleRequestExecutor;
 
 #ifdef DEBUG
   bool mSetOpenerWindowCalled;
   nsCOMPtr<nsIURI> mLastOpenedURI;
 #endif
 
-#ifdef MOZ_B2G
-  bool mNetworkUploadObserverEnabled;
-  bool mNetworkDownloadObserverEnabled;
-#endif // MOZ_B2G
-
   bool mCleanedUp;
 
   nsCOMPtr<nsIDOMOfflineResourceList> mApplicationCache;
@@ -1975,7 +1971,7 @@ protected:
 
   nsTArray<uint32_t> mEnabledSensors;
 
-#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
+#if defined(MOZ_WIDGET_ANDROID)
   nsAutoPtr<mozilla::dom::WindowOrientationObserver> mOrientationChangeObserver;
 #endif
 
@@ -2002,6 +1998,7 @@ protected:
   friend class nsDOMWindowUtils;
   friend class mozilla::dom::PostMessageEvent;
   friend class DesktopNotification;
+  friend class IdleRequestExecutor;
 
   static WindowByIdTable* sWindowsById;
   static bool sWarnedAboutWindowInternal;
diff --git a/dom/base/nsIContentPolicy.idl b/dom/base/nsIContentPolicy.idl
index a73565a9a..200b97fbc 100644
--- a/dom/base/nsIContentPolicy.idl
+++ b/dom/base/nsIContentPolicy.idl
@@ -20,7 +20,7 @@ interface nsIPrincipal;
  * by launching a dialog to prompt the user for something).
  */
 
-[scriptable,uuid(caad4f1f-d047-46ac-ae9d-dc598e4fb91b)]
+[scriptable,uuid(64a5ae16-6836-475c-9938-4b6cc1eee8fb)]
 interface nsIContentPolicy : nsIContentPolicyBase
 {
   /**
diff --git a/dom/base/nsIContentPolicyBase.idl b/dom/base/nsIContentPolicyBase.idl
index 884e3d96d..908e562a8 100644
--- a/dom/base/nsIContentPolicyBase.idl
+++ b/dom/base/nsIContentPolicyBase.idl
@@ -24,7 +24,7 @@ typedef unsigned long nsContentPolicyType;
  * by launching a dialog to prompt the user for something).
  */
 
-[scriptable,uuid(17418187-d86f-48dd-92d1-238838df0a4e)]
+[scriptable,uuid(d6ab1d11-8e24-4db4-8582-c40a78281737)]
 interface nsIContentPolicyBase : nsISupports
 {
   /**
@@ -329,11 +329,17 @@ interface nsIContentPolicyBase : nsISupports
    */
   const nsContentPolicyType TYPE_INTERNAL_IMAGE_FAVICON = 41;
 
+  /**
+   * Indicates an save-as link download from the front-end code.
+   */
+  const nsContentPolicyType TYPE_SAVEAS_DOWNLOAD = 42;
+
   /* When adding new content types, please update nsContentBlocker,
-   * NS_CP_ContentTypeName, nsCSPContext, all nsIContentPolicy
-   * implementations, the static_assert in dom/cache/DBSchema.cpp,
-   * and other things that are not listed here that are related to
-   * nsIContentPolicy. */
+   * NS_CP_ContentTypeName, nsCSPContext, CSP_ContentTypeToDirective,
+   * DoContentSecurityChecks, all nsIContentPolicy implementations, the
+   * static_assert in dom/cache/DBSchema.cpp, nsPermissionManager.cpp,
+   * and other things that are not listed here that are related
+   * to nsIContentPolicy. */
 
   //////////////////////////////////////////////////////////////////////
 
diff --git a/dom/base/nsIDocument.h b/dom/base/nsIDocument.h
index 8f35e9ba5..7a73fae71 100644
--- a/dom/base/nsIDocument.h
+++ b/dom/base/nsIDocument.h
@@ -18,11 +18,11 @@
 #include "nsINode.h"                     // for base class
 #include "nsIScriptGlobalObject.h"       // for member (in nsCOMPtr)
 #include "nsIServiceManager.h"
+#include "nsIURI.h"                      // for use in inline functions
 #include "nsIUUIDGenerator.h"
 #include "nsPIDOMWindow.h"               // for use in inline functions
 #include "nsPropertyTable.h"             // for member
-#include "nsDataHashtable.h"             // for member
-#include "nsURIHashKey.h"                // for member
+#include "nsTHashtable.h"                // for member
 #include "mozilla/net/ReferrerPolicy.h"  // for member
 #include "nsWeakReference.h"
 #include "mozilla/UseCounter.h"
@@ -151,6 +151,7 @@ class NodeIterator;
 enum class OrientationType : uint32_t;
 class ProcessingInstruction;
 class Promise;
+class Selection;
 class StyleSheetList;
 class SVGDocument;
 class SVGSVGElement;
@@ -181,13 +182,6 @@ enum DocumentFlavor {
   DocumentFlavorPlain, // Just a Document
 };
 
-// Enum for HSTS priming states
-enum class HSTSPrimingState {
-  eNO_HSTS_PRIMING = 0,    // don't do HSTS Priming
-  eHSTS_PRIMING_ALLOW = 1, // if HSTS priming fails, allow the load to proceed
-  eHSTS_PRIMING_BLOCK = 2  // if HSTS priming fails, block the load
-};
-
 // Document states
 
 // RTL locale: specific to the XUL localedir attribute
@@ -405,34 +399,6 @@ public:
   }
 
   /**
-   * Check to see if a subresource we want to load requires HSTS priming
-   * to be done.
-   */
-  HSTSPrimingState GetHSTSPrimingStateForLocation(nsIURI* aContentLocation) const
-  {
-    HSTSPrimingState state;
-    if (mHSTSPrimingURIList.Get(aContentLocation, &state)) {
-      return state;
-    }
-    return HSTSPrimingState::eNO_HSTS_PRIMING;
-  }
-
-  /**
-   * Add a subresource to the HSTS priming list. If this URI is
-   * not in the HSTS cache, it will trigger an HSTS priming request
-   * when we try to load it.
-   */
-  void AddHSTSPrimingLocation(nsIURI* aContentLocation, HSTSPrimingState aState)
-  {
-    mHSTSPrimingURIList.Put(aContentLocation, aState);
-  }
-
-  void ClearHSTSPrimingLocation(nsIURI* aContentLocation)
-  {
-    mHSTSPrimingURIList.Remove(aContentLocation);
-  }
-
-  /**
    * Set the principal responsible for this document.
    */
   virtual void SetPrincipal(nsIPrincipal *aPrincipal) = 0;
@@ -898,6 +864,8 @@ public:
    */
   Element* GetRootElement() const;
 
+  mozilla::dom::Selection* GetSelection(mozilla::ErrorResult& aRv);
+
   /**
    * Retrieve information about the viewport as a data structure.
    * This will return information in the viewport META data section
@@ -2984,11 +2952,6 @@ protected:
   bool mUpgradeInsecureRequests;
   bool mUpgradeInsecurePreloads;
 
-  // if nsMixedContentBlocker requires sending an HSTS priming request,
-  // temporarily store that in the document so that it can be propogated to the
-  // LoadInfo and eventually the HTTP Channel
-  nsDataHashtable<nsURIHashKey, HSTSPrimingState> mHSTSPrimingURIList;
-
   mozilla::WeakPtr<nsDocShell> mDocumentContainer;
 
   nsCString mCharacterSet;
diff --git a/dom/base/nsINode.cpp b/dom/base/nsINode.cpp
index 3a649a61d..09e848710 100644
--- a/dom/base/nsINode.cpp
+++ b/dom/base/nsINode.cpp
@@ -1777,8 +1777,8 @@ nsINode::Before(const Sequence<OwningNodeOrString>& aNodes,
   nsCOMPtr<nsINode> viablePreviousSibling =
     FindViablePreviousSibling(*this, aNodes);
 
-  nsCOMPtr<nsINode> node =
-    ConvertNodesOrStringsIntoNode(aNodes, OwnerDoc(), aRv);
+  nsCOMPtr<nsIDocument> doc = OwnerDoc();
+  nsCOMPtr<nsINode> node = ConvertNodesOrStringsIntoNode(aNodes, doc, aRv);
   if (aRv.Failed()) {
     return;
   }
@@ -1800,8 +1800,8 @@ nsINode::After(const Sequence<OwningNodeOrString>& aNodes,
 
   nsCOMPtr<nsINode> viableNextSibling = FindViableNextSibling(*this, aNodes);
 
-  nsCOMPtr<nsINode> node =
-    ConvertNodesOrStringsIntoNode(aNodes, OwnerDoc(), aRv);
+  nsCOMPtr<nsIDocument> doc = OwnerDoc();
+  nsCOMPtr<nsINode> node = ConvertNodesOrStringsIntoNode(aNodes, doc, aRv);
   if (aRv.Failed()) {
     return;
   }
@@ -1820,8 +1820,8 @@ nsINode::ReplaceWith(const Sequence<OwningNodeOrString>& aNodes,
 
   nsCOMPtr<nsINode> viableNextSibling = FindViableNextSibling(*this, aNodes);
 
-  nsCOMPtr<nsINode> node =
-    ConvertNodesOrStringsIntoNode(aNodes, OwnerDoc(), aRv);
+  nsCOMPtr<nsIDocument> doc = OwnerDoc();
+  nsCOMPtr<nsINode> node = ConvertNodesOrStringsIntoNode(aNodes, doc, aRv);
   if (aRv.Failed()) {
     return;
   }
@@ -1880,8 +1880,8 @@ void
 nsINode::Prepend(const Sequence<OwningNodeOrString>& aNodes,
                  ErrorResult& aRv)
 {
-  nsCOMPtr<nsINode> node =
-    ConvertNodesOrStringsIntoNode(aNodes, OwnerDoc(), aRv);
+  nsCOMPtr<nsIDocument> doc = OwnerDoc();
+  nsCOMPtr<nsINode> node = ConvertNodesOrStringsIntoNode(aNodes, doc, aRv);
   if (aRv.Failed()) {
     return;
   }
@@ -1894,8 +1894,8 @@ void
 nsINode::Append(const Sequence<OwningNodeOrString>& aNodes,
                  ErrorResult& aRv)
 {
-  nsCOMPtr<nsINode> node =
-    ConvertNodesOrStringsIntoNode(aNodes, OwnerDoc(), aRv);
+  nsCOMPtr<nsIDocument> doc = OwnerDoc();
+  nsCOMPtr<nsINode> node = ConvertNodesOrStringsIntoNode(aNodes, doc, aRv);
   if (aRv.Failed()) {
     return;
   }
@@ -1907,6 +1907,10 @@ void
 nsINode::doRemoveChildAt(uint32_t aIndex, bool aNotify,
                          nsIContent* aKid, nsAttrAndChildArray& aChildArray)
 {
+  // NOTE: This function must not trigger any calls to
+  // nsIDocument::GetRootElement() calls until *after* it has removed aKid from
+  // aChildArray. Any calls before then could potentially restore a stale
+  // value for our cached root element, per note in nsDocument::RemoveChildAt().
   NS_PRECONDITION(aKid && aKid->GetParentNode() == this &&
                   aKid == GetChildAt(aIndex) &&
                   IndexOf(aKid) == (int32_t)aIndex, "Bogus aKid");
diff --git a/dom/base/nsISelectionPrivate.idl b/dom/base/nsISelectionPrivate.idl
index 68412885e..049873b28 100644
--- a/dom/base/nsISelectionPrivate.idl
+++ b/dom/base/nsISelectionPrivate.idl
@@ -29,7 +29,7 @@ native nsDirection(nsDirection);
 native ScrollAxis(nsIPresShell::ScrollAxis);
 
 [scriptable, builtinclass, uuid(0c9f4f74-ee7e-4fe9-be6b-0ba856368178)]
-interface nsISelectionPrivate : nsISelection
+interface nsISelectionPrivate : nsISupports
  {
     const short ENDOFPRECEDINGLINE=0;
     const short STARTOFNEXTLINE=1;
diff --git a/dom/base/nsISimpleContentPolicy.idl b/dom/base/nsISimpleContentPolicy.idl
index 493aee1a5..dc0474736 100644
--- a/dom/base/nsISimpleContentPolicy.idl
+++ b/dom/base/nsISimpleContentPolicy.idl
@@ -28,7 +28,7 @@ interface nsIDOMElement;
  * by launching a dialog to prompt the user for something).
  */
 
-[scriptable,uuid(b9df71e3-a9b3-4706-b2d5-e6c0d3d68ec7)]
+[scriptable,uuid(1553a476-8a14-410b-8ecc-47f48e937392)]
 interface nsISimpleContentPolicy : nsIContentPolicyBase
 {
   /**
diff --git a/dom/base/nsJSEnvironment.cpp b/dom/base/nsJSEnvironment.cpp
index 576f3052a..3be1a6d2f 100644
--- a/dom/base/nsJSEnvironment.cpp
+++ b/dom/base/nsJSEnvironment.cpp
@@ -1006,110 +1006,6 @@ nsJSContext::AddSupportsPrimitiveTojsvals(nsISupports *aArg, JS::Value *aArgv)
   return NS_OK;
 }
 
-#ifdef MOZ_JPROF
-
-#include <signal.h>
-
-inline bool
-IsJProfAction(struct sigaction *action)
-{
-    return (action->sa_sigaction &&
-            (action->sa_flags & (SA_RESTART | SA_SIGINFO)) == (SA_RESTART | SA_SIGINFO));
-}
-
-void NS_JProfStartProfiling();
-void NS_JProfStopProfiling();
-void NS_JProfClearCircular();
-
-static bool
-JProfStartProfilingJS(JSContext *cx, unsigned argc, JS::Value *vp)
-{
-  NS_JProfStartProfiling();
-  return true;
-}
-
-void NS_JProfStartProfiling()
-{
-    // Figure out whether we're dealing with SIGPROF, SIGALRM, or
-    // SIGPOLL profiling (SIGALRM for JP_REALTIME, SIGPOLL for
-    // JP_RTC_HZ)
-    struct sigaction action;
-
-    // Must check ALRM before PROF since both are enabled for real-time
-    sigaction(SIGALRM, nullptr, &action);
-    //printf("SIGALRM: %p, flags = %x\n",action.sa_sigaction,action.sa_flags);
-    if (IsJProfAction(&action)) {
-        //printf("Beginning real-time jprof profiling.\n");
-        raise(SIGALRM);
-        return;
-    }
-
-    sigaction(SIGPROF, nullptr, &action);
-    //printf("SIGPROF: %p, flags = %x\n",action.sa_sigaction,action.sa_flags);
-    if (IsJProfAction(&action)) {
-        //printf("Beginning process-time jprof profiling.\n");
-        raise(SIGPROF);
-        return;
-    }
-
-    sigaction(SIGPOLL, nullptr, &action);
-    //printf("SIGPOLL: %p, flags = %x\n",action.sa_sigaction,action.sa_flags);
-    if (IsJProfAction(&action)) {
-        //printf("Beginning rtc-based jprof profiling.\n");
-        raise(SIGPOLL);
-        return;
-    }
-
-    printf("Could not start jprof-profiling since JPROF_FLAGS was not set.\n");
-}
-
-static bool
-JProfStopProfilingJS(JSContext *cx, unsigned argc, JS::Value *vp)
-{
-  NS_JProfStopProfiling();
-  return true;
-}
-
-void
-NS_JProfStopProfiling()
-{
-    raise(SIGUSR1);
-    //printf("Stopped jprof profiling.\n");
-}
-
-static bool
-JProfClearCircularJS(JSContext *cx, unsigned argc, JS::Value *vp)
-{
-  NS_JProfClearCircular();
-  return true;
-}
-
-void
-NS_JProfClearCircular()
-{
-    raise(SIGUSR2);
-    //printf("cleared jprof buffer\n");
-}
-
-static bool
-JProfSaveCircularJS(JSContext *cx, unsigned argc, JS::Value *vp)
-{
-  // Not ideal...
-  NS_JProfStopProfiling();
-  NS_JProfStartProfiling();
-  return true;
-}
-
-static const JSFunctionSpec JProfFunctions[] = {
-    JS_FS("JProfStartProfiling",        JProfStartProfilingJS,      0, 0),
-    JS_FS("JProfStopProfiling",         JProfStopProfilingJS,       0, 0),
-    JS_FS("JProfClearCircular",         JProfClearCircularJS,       0, 0),
-    JS_FS("JProfSaveCircular",          JProfSaveCircularJS,        0, 0),
-    JS_FS_END
-};
-
-#endif /* defined(MOZ_JPROF) */
-
 nsresult
 nsJSContext::InitClasses(JS::Handle<JSObject*> aGlobalObj)
 {
@@ -1121,11 +1017,6 @@ nsJSContext::InitClasses(JS::Handle<JSObject*> aGlobalObj)
   // Attempt to initialize profiling functions
   ::JS_DefineProfilingFunctions(cx, aGlobalObj);
 
-#ifdef MOZ_JPROF
-  // Attempt to initialize JProf functions
-  ::JS_DefineFunctions(cx, aGlobalObj, JProfFunctions);
-#endif
-
   return NS_OK;
 }
 
diff --git a/dom/base/nsNodeUtils.cpp b/dom/base/nsNodeUtils.cpp
index 69a9414fe..ecea95dc1 100644
--- a/dom/base/nsNodeUtils.cpp
+++ b/dom/base/nsNodeUtils.cpp
@@ -297,15 +297,6 @@ nsNodeUtils::LastRelease(nsINode* aNode)
                                          NodeWillBeDestroyed, (aNode));
     }
 
-    if (aNode->IsElement()) {
-      Element* elem = aNode->AsElement();
-      FragmentOrElement::nsDOMSlots* domSlots =
-        static_cast<FragmentOrElement::nsDOMSlots*>(slots);
-      for (auto& reg : domSlots->mRegisteredIntersectionObservers) {
-        reg.observer->UnlinkTarget(*elem);
-      }
-    }
-
     delete slots;
     aNode->mSlots = nullptr;
   }
diff --git a/dom/base/nsPIDOMWindow.h b/dom/base/nsPIDOMWindow.h
index 45823057a..47affbb06 100644
--- a/dom/base/nsPIDOMWindow.h
+++ b/dom/base/nsPIDOMWindow.h
@@ -444,7 +444,7 @@ public:
    */
   virtual void DisableDeviceSensor(uint32_t aType) = 0;
 
-#if defined(MOZ_WIDGET_ANDROID) || defined(MOZ_WIDGET_GONK)
+#if defined(MOZ_WIDGET_ANDROID)
   virtual void EnableOrientationChangeListener() = 0;
   virtual void DisableOrientationChangeListener() = 0;
 #endif
@@ -452,24 +452,6 @@ public:
   virtual void EnableTimeChangeNotifications() = 0;
   virtual void DisableTimeChangeNotifications() = 0;
 
-#ifdef MOZ_B2G
-  /**
-   * Tell the window that it should start to listen to the network event of the
-   * given aType.
-   *
-   * Inner windows only.
-   */
-  virtual void EnableNetworkEvent(mozilla::EventMessage aEventMessage) = 0;
-
-  /**
-   * Tell the window that it should stop to listen to the network event of the
-   * given aType.
-   *
-   * Inner windows only.
-   */
-  virtual void DisableNetworkEvent(mozilla::EventMessage aEventMessage) = 0;
-#endif // MOZ_B2G
-
   /**
    * Tell this window that there is an observer for gamepad input
    *
diff --git a/dom/base/nsStructuredCloneContainer.cpp b/dom/base/nsStructuredCloneContainer.cpp
index 8c2cdc091..ea2d38bc8 100644
--- a/dom/base/nsStructuredCloneContainer.cpp
+++ b/dom/base/nsStructuredCloneContainer.cpp
@@ -137,7 +137,7 @@ nsStructuredCloneContainer::GetDataAsBase64(nsAString &aOut)
     return NS_ERROR_FAILURE;
   }
 
-  auto iter = Data().Iter();
+  auto iter = Data().Start();
   size_t size = Data().Size();
   nsAutoCString binaryData;
   binaryData.SetLength(size);
diff --git a/dom/base/test/bug704320.sjs b/dom/base/test/bug704320.sjs
index dff77f4b3..e0f549533 100644
--- a/dom/base/test/bug704320.sjs
+++ b/dom/base/test/bug704320.sjs
@@ -194,12 +194,6 @@ function createPolicyTest(policy, optionalEarlierPolicy) {
 }
 
 function handleRequest(request, response) {
-  if (request.method == 'HEAD') {
-    // respond to a HEAD request with a 418 so that we can easily distinguish
-    // HSTS priming responses and ignore them
-    response.setStatusLine('1.1', 418, "I'm a teapot");
-    return;
-  }
   var sharedKey = 'bug704320.sjs';
   var params = request.queryString.split('&');
   var action = params[0].split('=')[1];
diff --git a/dom/base/test/file_ipc_messagemanager_blob.html b/dom/base/test/file_ipc_messagemanager_blob.html
new file mode 100644
index 000000000..dbdd64a34
--- /dev/null
+++ b/dom/base/test/file_ipc_messagemanager_blob.html
@@ -0,0 +1 @@
+<!DOCTYPE HTML><html><body></body></html>
diff --git a/dom/base/test/file_simplecontentpolicy.js b/dom/base/test/file_simplecontentpolicy.js
index 1f9606c49..2727b9530 100644
--- a/dom/base/test/file_simplecontentpolicy.js
+++ b/dom/base/test/file_simplecontentpolicy.js
@@ -39,7 +39,6 @@ var policy = {
   {
     // Remember last content type seen for the test url
     if (contentLocation.spec.endsWith(urlSuffix)) {
-      assert.ok(frame === browserElement, "correct <browser> element");
       sendAsyncMessage("shouldLoad", {contentType: contentType, isTopLevel: isTopLevel});
       return Ci.nsIContentPolicy.REJECT_REQUEST;
     }
diff --git a/dom/base/test/mochitest.ini b/dom/base/test/mochitest.ini
index ddfd57443..b3b804ce4 100644
--- a/dom/base/test/mochitest.ini
+++ b/dom/base/test/mochitest.ini
@@ -676,6 +676,7 @@ skip-if = (toolkit == 'android') # Android: Bug 775227
 [test_intersectionobservers.html]
 skip-if = true # Track Bug 1320704
 [test_ipc_messagemanager_blob.html]
+support-files = file_ipc_messagemanager_blob.html
 [test_link_prefetch.html]
 skip-if = !e10s # Track Bug 1281415
 [test_link_stylesheet.html]
diff --git a/dom/base/test/referrerHelper.js b/dom/base/test/referrerHelper.js
index 207bf5f15..01a22829c 100644
--- a/dom/base/test/referrerHelper.js
+++ b/dom/base/test/referrerHelper.js
@@ -25,9 +25,6 @@ function doXHR(url, onSuccess, onFail) {
   xhr.onload = function () {
     if (xhr.status == 200) {
       onSuccess(xhr);
-    } else if (xhr.status == 418) {
-      // Ignore HSTS priming responses
-      return;
     } else {
       onFail(xhr);
     }
diff --git a/dom/base/test/test_intersectionobservers.html b/dom/base/test/test_intersectionobservers.html
index e7875e3af..10e3d7712 100644
--- a/dom/base/test/test_intersectionobservers.html
+++ b/dom/base/test/test_intersectionobservers.html
@@ -325,7 +325,7 @@ limitations under the License.
       });
 
 
-      it('does not trigger if target does not intersect when observing begins',
+      it('does trigger if target does not intersect when observing begins',
           function(done) {
 
         var spy = sinon.spy();
@@ -334,7 +334,7 @@ limitations under the License.
         targetEl2.style.top = '-40px';
         io.observe(targetEl2);
         callDelayed(function() {
-          expect(spy.callCount).to.be(0);
+          expect(spy.callCount).to.be(1);
           done();
         }, ASYNC_TIMEOUT);
       });
@@ -528,7 +528,7 @@ limitations under the License.
             spy.waitForNotification(function() {
               expect(spy.callCount).to.be(1);
               var records = sortRecords(spy.lastCall.args[0]);
-              expect(records.length).to.be(2);
+              expect(records.length).to.be(3);
               expect(records[0].target).to.be(targetEl1);
               expect(records[0].intersectionRatio).to.be(0.25);
               expect(records[1].target).to.be(targetEl2);
@@ -636,10 +636,10 @@ limitations under the License.
               expect(records.length).to.be(3);
               expect(records[0].target).to.be(targetEl1);
               expect(records[0].intersectionRatio).to.be(0.5);
-              expect(records[1].target).to.be(targetEl3);
-              expect(records[1].intersectionRatio).to.be(0.5);
-              expect(records[2].target).to.be(targetEl4);
+              expect(records[2].target).to.be(targetEl3);
               expect(records[2].intersectionRatio).to.be(0.5);
+              expect(records[3].target).to.be(targetEl4);
+              expect(records[3].intersectionRatio).to.be(0.5);
               io.disconnect();
               done();
             }, {root: rootEl, rootMargin: '-10px 10%'});
@@ -652,11 +652,11 @@ limitations under the License.
           function(done) {
             io = new IntersectionObserver(function(records) {
               records = sortRecords(records);
-              expect(records.length).to.be(2);
+              expect(records.length).to.be(4);
               expect(records[0].target).to.be(targetEl1);
               expect(records[0].intersectionRatio).to.be(0.5);
-              expect(records[1].target).to.be(targetEl4);
-              expect(records[1].intersectionRatio).to.be(0.5);
+              expect(records[3].target).to.be(targetEl4);
+              expect(records[3].intersectionRatio).to.be(0.5);
               io.disconnect();
               done();
             }, {root: rootEl, rootMargin: '-5% -2.5% 0px'});
@@ -669,13 +669,13 @@ limitations under the License.
           function(done) {
             io = new IntersectionObserver(function(records) {
               records = sortRecords(records);
-              expect(records.length).to.be(3);
+              expect(records.length).to.be(4);
               expect(records[0].target).to.be(targetEl1);
               expect(records[0].intersectionRatio).to.be(0.5);
               expect(records[1].target).to.be(targetEl2);
               expect(records[1].intersectionRatio).to.be(0.5);
-              expect(records[2].target).to.be(targetEl4);
-              expect(records[2].intersectionRatio).to.be(0.25);
+              expect(records[3].target).to.be(targetEl4);
+              expect(records[3].intersectionRatio).to.be(0.25);
               io.disconnect();
               done();
             }, {root: rootEl, rootMargin: '5% -2.5% -10px -190px'});
@@ -705,9 +705,9 @@ limitations under the License.
             spy.waitForNotification(function() {
               expect(spy.callCount).to.be(1);
               var records = sortRecords(spy.lastCall.args[0]);
-              expect(records.length).to.be(1);
-              expect(records[0].intersectionRatio).to.be(0);
-              expect(records[0].target).to.be(targetEl2);
+              expect(records.length).to.be(2);
+              expect(records[1].intersectionRatio).to.be(0);
+              expect(records[1].target).to.be(targetEl2);
               done();
             }, ASYNC_TIMEOUT);
           },
@@ -797,14 +797,14 @@ limitations under the License.
           function(done) {
             document.getElementById('fixtures').appendChild(rootEl);
             callDelayed(function() {
-              expect(spy.callCount).to.be(0);
+              expect(spy.callCount).to.be(1);
               done();
             }, ASYNC_TIMEOUT);
           },
           function(done) {
             parentEl.insertBefore(targetEl1, targetEl2);
             spy.waitForNotification(function() {
-              expect(spy.callCount).to.be(1);
+              expect(spy.callCount).to.be(2);
               var records = sortRecords(spy.lastCall.args[0]);
               expect(records.length).to.be(1);
               expect(records[0].intersectionRatio).to.be(1);
@@ -815,7 +815,7 @@ limitations under the License.
           function(done) {
             grandParentEl.parentNode.removeChild(grandParentEl);
             spy.waitForNotification(function() {
-              expect(spy.callCount).to.be(2);
+              expect(spy.callCount).to.be(3);
               var records = sortRecords(spy.lastCall.args[0]);
               expect(records.length).to.be(1);
               expect(records[0].intersectionRatio).to.be(0);
@@ -826,7 +826,7 @@ limitations under the License.
           function(done) {
             rootEl.appendChild(targetEl1);
             spy.waitForNotification(function() {
-              expect(spy.callCount).to.be(3);
+              expect(spy.callCount).to.be(4);
               var records = sortRecords(spy.lastCall.args[0]);
               expect(records.length).to.be(1);
               expect(records[0].intersectionRatio).to.be(1);
@@ -837,7 +837,7 @@ limitations under the License.
           function(done) {
             rootEl.parentNode.removeChild(rootEl);
             spy.waitForNotification(function() {
-              expect(spy.callCount).to.be(4);
+              expect(spy.callCount).to.be(5);
               var records = sortRecords(spy.lastCall.args[0]);
               expect(records.length).to.be(1);
               expect(records[0].intersectionRatio).to.be(0);
@@ -867,8 +867,14 @@ limitations under the License.
 
         targetEl1.style.top = '220px';
         targetEl1.style.left = '220px';
+        
+        var callCount = 0;
 
         io = new IntersectionObserver(function(records) {
+          callCount++;
+          if (callCount <= 1) {
+            return;
+          }
           expect(records.length).to.be(1);
           expect(records[0].intersectionRatio).to.be(1);
           done();
@@ -891,6 +897,19 @@ limitations under the License.
         var win = window.open("intersectionobserver_window.html");
       });
 
+      it('triggers only once if observed multiple times (and does not crash when collected)', function(done) {
+        var spy = sinon.spy();
+        io = new IntersectionObserver(spy, {root: rootEl});
+        io.observe(targetEl1);
+        io.observe(targetEl1);
+        io.observe(targetEl1);
+
+        callDelayed(function () {
+          expect(spy.callCount).to.be(1);
+          done();
+        }, ASYNC_TIMEOUT);
+      });
+
     });
 
     describe('observe subframe', function () {
diff --git a/dom/base/test/test_ipc_messagemanager_blob.html b/dom/base/test/test_ipc_messagemanager_blob.html
index 74eab2945..77d6c767f 100644
--- a/dom/base/test/test_ipc_messagemanager_blob.html
+++ b/dom/base/test/test_ipc_messagemanager_blob.html
@@ -14,8 +14,7 @@
 
     SimpleTest.waitForExplicitFinish();
 
-    const childFrameURL =
-      "data:text/html,<!DOCTYPE HTML><html><body></body></html>";
+    const childFrameURL = "file_ipc_messagemanager_blob.html";
 
     function childFrameScript() {
       "use strict";
diff --git a/dom/base/test/test_x-frame-options.html b/dom/base/test/test_x-frame-options.html
index 8e24d8a78..a0c7acdc3 100644
--- a/dom/base/test/test_x-frame-options.html
+++ b/dom/base/test/test_x-frame-options.html
@@ -147,7 +147,11 @@ var testFrameInDataURI = function() {
 SimpleTest.waitForExplicitFinish();
 
 // load the test harness
-document.getElementById("harness").src = "file_x-frame-options_main.html";
+SpecialPowers.pushPrefEnv({
+  "set": [["security.data_uri.block_toplevel_data_uri_navigations", false],]
+}, function() {
+  document.getElementById("harness").src = "file_x-frame-options_main.html";
+});
 
 </script>
 </pre>