Support GestureBegin and GestureEnd in ui::GestureProvider

ui/events/gesture_detection/gesture_provider.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_EVENTS_GESTURE_DETECTION_GESTURE_PROVIDER_H_
 #define UI_EVENTS_GESTURE_DETECTION_GESTURE_PROVIDER_H_
 
 #include "base/basictypes.h"
 #include "base/memory/scoped_ptr.h"
 #include "ui/events/gesture_detection/gesture_detection_export.h"
@@ skipping 14 matching lines @@
 // Given a stream of |MotionEvent|'s, provides gesture detection and gesture
 // event dispatch.
 class GESTURE_DETECTION_EXPORT GestureProvider {
  public:
   struct GESTURE_DETECTION_EXPORT Config {
     Config();
     ~Config();
     GestureDetector::Config gesture_detector_config;
     ScaleGestureDetector::Config scale_gesture_detector_config;
     SnapScrollController::Config snap_scroll_controller_config;
+
+    // If |disable_click_delay| is true and double-tap support is disabled,
+    // there will be no delay before tap events. When double-tap support is
+    // enabled, there will always be a delay before a tap event is fired, in
+    // order to allow the double tap gesture to occur without firing any tap
+    // events.
     bool disable_click_delay;
+
+    // If |gesture_begin_end_types_enabled| is true, fire an ET_GESTURE_BEGIN
+    // event for every added touch point, and an ET_GESTURE_END event for every
+    // removed touch point.
+    bool gesture_begin_end_types_enabled;
   };
 
   GestureProvider(const Config& config, GestureProviderClient* client);
   ~GestureProvider();
 
   // Handle the incoming MotionEvent, returning false if the event could not
   // be handled.
   bool OnTouchEvent(const MotionEvent& event);
 
   // Resets all gesture detectors; called on DidStartLoading().
@@ skipping 41 matching lines @@
 
   bool CanHandle(const MotionEvent& event) const;
 
   void Fling(const MotionEvent& e, float velocity_x, float velocity_y);
   void Send(const GestureEventData& gesture);
   void SendTapCancelIfNecessary(const MotionEvent& event);
   void SendTapCancelIfNecessary(const GestureEventData& event);
   bool SendLongTapIfNecessary(const MotionEvent& event);
   void EndTouchScrollIfNecessary(const MotionEvent& event,
                                  bool send_scroll_end_event);
+  void OnTouchEventHandlingBegin(const MotionEvent& event);
+  void OnTouchEventHandlingEnd(const MotionEvent& event);
   void UpdateDoubleTapDetectionSupport();
 
   GestureProviderClient* const client_;
 
   class GestureListenerImpl;
   friend class GestureListenerImpl;
   scoped_ptr<GestureListenerImpl> gesture_listener_;
 
   class ScaleGestureListenerImpl;
   friend class ScaleGestureListenerImpl;
@@ skipping 16 matching lines @@
   bool pinch_in_progress_;
 
   // Whether double-tap gesture detection is currently supported.
   bool double_tap_support_for_page_;
   bool double_tap_support_for_platform_;
 
   // Keeps track of the current GESTURE_LONG_PRESS event. If a context menu is
   // opened after a GESTURE_LONG_PRESS, this is used to insert a
   // GESTURE_TAP_CANCEL for removing any ::active styling.
   base::TimeTicks current_longpress_time_;
+
+  bool gesture_begin_end_types_enabled_;
 };
 
 }  //  namespace ui
 
 #endif  // UI_EVENTS_GESTURE_DETECTION_GESTURE_PROVIDER_H_