Add touch scrolling modes experimental flags (DEPRECATED)

content/browser/renderer_host/input/gesture_event_queue.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 CONTENT_BROWSER_RENDERER_HOST_INPUT_GESTURE_EVENT_QUEUE_H_
 #define CONTENT_BROWSER_RENDERER_HOST_INPUT_GESTURE_EVENT_QUEUE_H_
 
 #include <deque>
 #include <queue>
 
@@ skipping 45 matching lines @@
     void UpdateState(InputEventAckState ack_state);
     bool IsGesturePrevented() const;
     bool IsEmpty() const;
 
    private:
     std::queue<GestureEventPacket> packets_;
     enum GestureHandlingState {
       PENDING,                 // The sequence has yet to receive an ack.
       ALLOWED_UNTIL_PREVENTED, // Gestures in the sequence are allowed until
                                // a source touch is preventDefault'ed.
-      ALWAYS_ALLOWED,          // All remaining sequence gestures are forwarded.
-      ALWAYS_PREVENTED         // All remaining sequence gestures are dropped.
+      ALWAYS_ALLOWED,          // All remaining sequence gestures are forwarded
+                               // except for independent packets whose
+                               // corresponding touch was consumed.
+      ALWAYS_PREVENTED         // All remaining sequence gestures are dropped,
+                               // except for 'ending' gestures which are
+                               // needed to complete a previous sequence.
     };
     GestureHandlingState state_;
   };
   void UpdateAndDispatchPackets(GestureSequence* sequence,
                                 InputEventAckState ack_result);
-  void SendPacket(const GestureEventPacket& packet);
+  void FilterAndSendPacket(const GestureEventPacket& packet,
+                           bool gesturePrevented,
+                           InputEventAckState ack_state);
   void SendGesture(const blink::WebGestureEvent& gesture);
   void CancelTapIfNecessary();
   void CancelFlingIfNecessary();
   GestureSequence& Head();
   GestureSequence& Tail();
 
   GestureEventQueueClient* client_;
   std::queue<GestureSequence> sequences_;
 
   // Bookkeeping for inserting synthetic Gesture{Tap,Fling}Cancel events
   // when necessary, e.g., GestureTapCancel when scrolling begins, or
   // GestureFlingCancel when a user taps following a GestureFlingStart.
   bool needs_tap_ending_event_;
   bool needs_fling_ending_event_;
 
+  // Bookkeeping to ensure that scroll/pinch sequences are terminated
+  // whenever they are started, regardless of the disposition.
+  bool needs_scroll_ending_event_;
+  bool needs_pinch_ending_event_;
+
   DISALLOW_COPY_AND_ASSIGN(GestureEventQueue);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_INPUT_GESTURE_EVENT_QUEUE_H_