Add m-esr52 at 52.6.0

1 files changed, 226 insertions, 0 deletions

diff --git a/layout/base/AccessibleCaretEventHub.h b/layout/base/AccessibleCaretEventHub.h
new file mode 100644
index 000000000..6681f8669
--- /dev/null
+++ b/layout/base/AccessibleCaretEventHub.h
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+/* -*- 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/. */
+
+#ifndef AccessibleCaretEventHub_h
+#define AccessibleCaretEventHub_h
+
+#include "mozilla/EventForwards.h"
+#include "mozilla/UniquePtr.h"
+#include "mozilla/WeakPtr.h"
+#include "nsCOMPtr.h"
+#include "nsIFrame.h"
+#include "nsIReflowObserver.h"
+#include "nsIScrollObserver.h"
+#include "nsISelectionListener.h"
+#include "nsPoint.h"
+#include "mozilla/RefPtr.h"
+#include "nsWeakReference.h"
+
+class nsDocShell;
+class nsIPresShell;
+class nsITimer;
+
+namespace mozilla {
+class AccessibleCaretManager;
+class WidgetKeyboardEvent;
+class WidgetMouseEvent;
+class WidgetTouchEvent;
+
+// -----------------------------------------------------------------------------
+// Each PresShell holds a shared pointer to an AccessibleCaretEventHub; each
+// AccessibleCaretEventHub holds a unique pointer to an AccessibleCaretManager.
+// Thus, there's one AccessibleCaretManager per PresShell.
+//
+// AccessibleCaretEventHub implements a state pattern. It receives events from
+// PresShell and callbacks by observers and listeners, and then relays them to
+// the current concrete state which calls necessary event-handling methods in
+// AccessibleCaretManager.
+//
+// We separate AccessibleCaretEventHub from AccessibleCaretManager to make the
+// state transitions in AccessibleCaretEventHub testable. We put (nearly) all
+// the operations involving PresShell, Selection, and AccessibleCaret
+// manipulation in AccessibleCaretManager so that we can mock methods in
+// AccessibleCaretManager in gtest. We test the correctness of the state
+// transitions by giving events, callbacks, and the return values by mocked
+// methods of AccessibleCaretEventHub. See TestAccessibleCaretEventHub.cpp.
+//
+// Besides dealing with real events, AccessibleCaretEventHub could also
+// synthesize fake long-tap events and inject those events to itself on the
+// platform lacks eMouseLongTap. Turn on this preference
+// "layout.accessiblecaret.use_long_tap_injector" for the fake long-tap events.
+//
+// State transition diagram:
+// http://hg.mozilla.org/mozilla-central/raw-file/default/layout/base/doc/AccessibleCaretEventHubStates.png
+// Source code of the diagram:
+// http://hg.mozilla.org/mozilla-central/file/default/layout/base/doc/AccessibleCaretEventHubStates.dot
+//
+// Please see the wiki page for more information.
+// https://wiki.mozilla.org/AccessibleCaret
+//
+class AccessibleCaretEventHub : public nsIReflowObserver,
+                                public nsIScrollObserver,
+                                public nsISelectionListener,
+                                public nsSupportsWeakReference
+{
+public:
+  explicit AccessibleCaretEventHub(nsIPresShell* aPresShell);
+  void Init();
+  void Terminate();
+
+  nsEventStatus HandleEvent(WidgetEvent* aEvent);
+
+  // Call this function to notify the blur event happened.
+  void NotifyBlur(bool aIsLeavingDocument);
+
+  NS_DECL_ISUPPORTS
+  NS_DECL_NSIREFLOWOBSERVER
+  NS_DECL_NSISELECTIONLISTENER
+
+  // Override nsIScrollObserver methods.
+  virtual void ScrollPositionChanged() override;
+  virtual void AsyncPanZoomStarted() override;
+  virtual void AsyncPanZoomStopped() override;
+
+  // Base state
+  class State;
+  State* GetState() const;
+
+protected:
+  virtual ~AccessibleCaretEventHub();
+
+#define MOZ_DECL_STATE_CLASS_GETTER(aClassName)                                \
+  class aClassName;                                                            \
+  static State* aClassName();
+
+#define MOZ_IMPL_STATE_CLASS_GETTER(aClassName)                                \
+  AccessibleCaretEventHub::State* AccessibleCaretEventHub::aClassName()        \
+  {                                                                            \
+    static class aClassName singleton;                                         \
+    return &singleton;                                                         \
+  }
+
+  // Concrete state getters
+  MOZ_DECL_STATE_CLASS_GETTER(NoActionState)
+  MOZ_DECL_STATE_CLASS_GETTER(PressCaretState)
+  MOZ_DECL_STATE_CLASS_GETTER(DragCaretState)
+  MOZ_DECL_STATE_CLASS_GETTER(PressNoCaretState)
+  MOZ_DECL_STATE_CLASS_GETTER(ScrollState)
+  MOZ_DECL_STATE_CLASS_GETTER(PostScrollState)
+  MOZ_DECL_STATE_CLASS_GETTER(LongTapState)
+
+  void SetState(State* aState);
+
+  nsEventStatus HandleMouseEvent(WidgetMouseEvent* aEvent);
+  nsEventStatus HandleTouchEvent(WidgetTouchEvent* aEvent);
+  nsEventStatus HandleKeyboardEvent(WidgetKeyboardEvent* aEvent);
+
+  virtual nsPoint GetTouchEventPosition(WidgetTouchEvent* aEvent,
+                                        int32_t aIdentifier) const;
+  virtual nsPoint GetMouseEventPosition(WidgetMouseEvent* aEvent) const;
+
+  bool MoveDistanceIsLarge(const nsPoint& aPoint) const;
+
+  void LaunchLongTapInjector();
+  void CancelLongTapInjector();
+  static void FireLongTap(nsITimer* aTimer, void* aAccessibleCaretEventHub);
+
+  void LaunchScrollEndInjector();
+  void CancelScrollEndInjector();
+  static void FireScrollEnd(nsITimer* aTimer, void* aAccessibleCaretEventHub);
+
+  // Member variables
+  State* mState = NoActionState();
+
+  // Will be set to nullptr in Terminate().
+  nsIPresShell* MOZ_NON_OWNING_REF mPresShell = nullptr;
+
+  UniquePtr<AccessibleCaretManager> mManager;
+
+  WeakPtr<nsDocShell> mDocShell;
+
+  // Use this timer for injecting a long tap event when APZ is disabled. If APZ
+  // is enabled, it will send long tap event to us.
+  nsCOMPtr<nsITimer> mLongTapInjectorTimer;
+
+  // Use this timer for injecting a simulated scroll end.
+  nsCOMPtr<nsITimer> mScrollEndInjectorTimer;
+
+  // Last mouse button down event or touch start event point.
+  nsPoint mPressPoint{ NS_UNCONSTRAINEDSIZE, NS_UNCONSTRAINEDSIZE };
+
+  // For filter multitouch event
+  int32_t mActiveTouchId = kInvalidTouchId;
+
+  // Flag to indicate the class has been initialized.
+  bool mInitialized = false;
+
+  // Flag to avoid calling Reflow() callback recursively.
+  bool mIsInReflowCallback = false;
+
+  // Simulate long tap if the platform does not support eMouseLongTap events.
+  static bool sUseLongTapInjector;
+
+  static const int32_t kScrollEndTimerDelay = 300;
+  static const int32_t kMoveStartToleranceInPixel = 5;
+  static const int32_t kInvalidTouchId = -1;
+  static const int32_t kDefaultTouchId = 0; // For mouse event
+};
+
+// -----------------------------------------------------------------------------
+// The base class for concrete states. A concrete state should inherit from this
+// class, and override the methods to handle the events or callbacks. A concrete
+// state is also responsible for transforming itself to the next concrete state.
+//
+class AccessibleCaretEventHub::State
+{
+public:
+  virtual const char* Name() const { return ""; }
+
+  virtual nsEventStatus OnPress(AccessibleCaretEventHub* aContext,
+                                const nsPoint& aPoint, int32_t aTouchId,
+                                EventClassID aEventClass)
+  {
+    return nsEventStatus_eIgnore;
+  }
+
+  virtual nsEventStatus OnMove(AccessibleCaretEventHub* aContext,
+                               const nsPoint& aPoint)
+  {
+    return nsEventStatus_eIgnore;
+  }
+
+  virtual nsEventStatus OnRelease(AccessibleCaretEventHub* aContext)
+  {
+    return nsEventStatus_eIgnore;
+  }
+
+  virtual nsEventStatus OnLongTap(AccessibleCaretEventHub* aContext,
+                                  const nsPoint& aPoint)
+  {
+    return nsEventStatus_eIgnore;
+  }
+
+  virtual void OnScrollStart(AccessibleCaretEventHub* aContext) {}
+  virtual void OnScrollEnd(AccessibleCaretEventHub* aContext) {}
+  virtual void OnScrollPositionChanged(AccessibleCaretEventHub* aContext) {}
+  virtual void OnBlur(AccessibleCaretEventHub* aContext,
+                      bool aIsLeavingDocument) {}
+  virtual void OnSelectionChanged(AccessibleCaretEventHub* aContext,
+                                  nsIDOMDocument* aDoc, nsISelection* aSel,
+                                  int16_t aReason) {}
+  virtual void OnReflow(AccessibleCaretEventHub* aContext) {}
+  virtual void Enter(AccessibleCaretEventHub* aContext) {}
+  virtual void Leave(AccessibleCaretEventHub* aContext) {}
+
+  explicit State() = default;
+  virtual ~State() = default;
+  State(const State&) = delete;
+  State& operator=(const State&) = delete;
+};
+
+} // namespace mozilla
+
+#endif // AccessibleCaretEventHub_h