Add touch drag UMA latency metric.

content/browser/renderer_host/render_widget_host_impl.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 CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_
 #define CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 589 matching lines @@
                              const base::TimeTicks& paint_start);
 
   // Give key press listeners a chance to handle this key press. This allow
   // widgets that don't have focus to still handle key presses.
   bool KeyPressListenersHandleEvent(const NativeWebKeyboardEvent& event);
 
   // InputRouterClient
   InputEventAckState FilterInputEvent(
       const blink::WebInputEvent& event,
       const ui::LatencyInfo& latency_info) override;
+  void OnForwardEventToRenderer(const blink::WebInputEvent& input_event,
+                                ui::LatencyInfo* latency_info) override;
+
   void IncrementInFlightEventCount() override;
   void DecrementInFlightEventCount() override;
   void OnHasTouchEventHandlers(bool has_handlers) override;
   void DidFlush() override;
   void DidOverscroll(const DidOverscrollParams& params) override;
   void DidStopFlinging() override;
 
   // InputAckHandler
   void OnKeyboardEventAck(const NativeWebKeyboardEventWithLatencyInfo& event,
                           InputEventAckState ack_result) override;
@@ skipping 202 matching lines @@
   base::TimeDelta new_content_rendering_delay_;
 
   base::WeakPtrFactory<RenderWidgetHostImpl> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(RenderWidgetHostImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_RENDER_WIDGET_HOST_IMPL_H_