Refcount touch tracking ids to prevent freeing them too early.

ui/events/event_utils.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_EVENTS_EVENT_UTILS_H_
 #define UI_EVENTS_EVENT_UTILS_H_
 
 #include "base/event_types.h"
 #include "base/memory/scoped_ptr.h"
 #include "ui/events/event_constants.h"
@@ skipping 88 matching lines @@
 base::NativeEvent CopyNativeEvent(
     const base::NativeEvent& native_event);
 
 // Delete a |native_event| previously created by CopyNativeEvent().
 void ReleaseCopiedNativeEvent(
     const base::NativeEvent& native_event);
 
 // Gets the touch id from a native event.
 EVENTS_EXPORT int GetTouchId(const base::NativeEvent& native_event);
 
+// Increases the number of times |ClearTouchIdIfReleased| needs to be called on
+// an event with a given touch id before it will actually be cleared.
+EVENTS_EXPORT void IncrementTouchIdRefCount(
+    const base::NativeEvent& native_event);
+
 // Clear the touch id from bookkeeping if it is a release/cancel event.
 EVENTS_EXPORT void ClearTouchIdIfReleased(
     const base::NativeEvent& native_event);
 
 // Gets the radius along the X/Y axis from a native event. Default is 1.0.
 EVENTS_EXPORT float GetTouchRadiusX(const base::NativeEvent& native_event);
 EVENTS_EXPORT float GetTouchRadiusY(const base::NativeEvent& native_event);
 
 // Gets the angle of the major axis away from the X axis. Default is 0.0.
 EVENTS_EXPORT float GetTouchAngle(const base::NativeEvent& native_event);
@@ skipping 43 matching lines @@
 EVENTS_EXPORT LPARAM GetLParamFromScanCode(uint16 scan_code);
 
 #endif
 
 // Registers a custom event type.
 EVENTS_EXPORT int RegisterCustomEventType();
 
 }  // namespace ui
 
 #endif  // UI_EVENTS_EVENT_UTILS_H_