Pass tap count (1 or 2) with tap gesture events

ui/base/gestures/gesture_types.h

 // Copyright (c) 2012 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_BASE_GESTURES_GESTURE_TYPES_H_
 #define UI_BASE_GESTURES_GESTURE_TYPES_H_
 
 #include "base/logging.h"
 #include "base/time.h"
 #include "ui/base/events.h"
@@ skipping 51 matching lines @@
   }
   bool swipe_up() const {
     CHECK_EQ(ui::ET_GESTURE_MULTIFINGER_SWIPE, type_);
     return data.swipe.up;
   }
   bool swipe_down() const {
     CHECK_EQ(ui::ET_GESTURE_MULTIFINGER_SWIPE, type_);
     return data.swipe.down;
   }
 
-  float generic_x() const {
-    return data.generic.delta_x;
-  }
-
-  float generic_y() const {
-    return data.generic.delta_y;
+  int tap_count() const {
+    CHECK_EQ(ui::ET_GESTURE_TAP, type_);
+    return data.tap_count;
   }
 
  private:
   ui::EventType type_;
   union {
     struct {  // SCROLL delta.
       float x;
       float y;
     } scroll;
 
     float scale;  // PINCH scale.
 
     struct {  // FLING velocity.
       float x;
       float y;
     } velocity;
 
     int touch_id;  // LONG_PRESS touch-id.
 
     struct {  // SWIPE direction.
       bool left;
       bool right;
       bool up;
       bool down;
     } swipe;
 
+    int tap_count;  // TAP repeat count.
+
     struct {
       float delta_x;
       float delta_y;
     } generic;
   } data;
 
   int touch_points_;  // Number of active touch points in the gesture.
 
   // Bounding box is an axis-aligned rectangle that contains all the
   // enclosing rectangles of the touch-points in the gesture.
@@ skipping 78 matching lines @@
                                        int touch_id,
                                        base::TimeDelta time_stamp) = 0;
 
   virtual bool DispatchLongPressGestureEvent(GestureEvent* event) = 0;
   virtual bool DispatchCancelTouchEvent(TouchEvent* event) = 0;
 };
 
 }  // namespace ui
 
 #endif  // UI_BASE_GESTURES_GESTURE_TYPES_H_