Move the TouchEventQueue to be completely virtual.

content/browser/renderer_host/input/input_router_impl.h

 // Copyright 2013 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_INPUT_ROUTER_IMPL_H_
 #define CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_IMPL_H_
 
 #include <stdint.h>
 
 #include <memory>
@@ skipping 234 matching lines @@
   // Whether there are any active flings in the renderer. As the fling
   // end notification is asynchronous, we use a count rather than a boolean
   // to avoid races in bookkeeping when starting a new fling.
   int active_renderer_fling_count_;
 
   // Whether the TouchScrollStarted event has been sent for the current
   // gesture scroll yet.
   bool touch_scroll_started_sent_;
 
   MouseWheelEventQueue wheel_event_queue_;
-  TouchEventQueue touch_event_queue_;
+  std::unique_ptr<TouchEventQueue> touch_event_queue_;
   GestureEventQueue gesture_event_queue_;
   TouchActionFilter touch_action_filter_;
   InputEventStreamValidator input_stream_validator_;
   InputEventStreamValidator output_stream_validator_;
 
   float device_scale_factor_;
 
   DISALLOW_COPY_AND_ASSIGN(InputRouterImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_INPUT_INPUT_ROUTER_IMPL_H_