Add support for latency measurement to Telemetry smoothness benchmarks.

content/browser/renderer_host/render_widget_host_impl.cc

 // 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.
 
 #include "content/browser/renderer_host/render_widget_host_impl.h"
 
 #include <math.h>
 #include <utility>
 
 #include "base/auto_reset.h"
@@ skipping 2484 matching lines @@
     return;
 
   OnRenderAutoResized(new_size);
 }
 
 void RenderWidgetHostImpl::DetachDelegate() {
   delegate_ = NULL;
 }
 
 void RenderWidgetHostImpl::FrameSwapped(const ui::LatencyInfo& latency_info) {
+  ui::LatencyInfo::LatencyMap::const_iterator l =
+      latency_info.latency_components.find(std::make_pair(
+          ui::INPUT_EVENT_LATENCY_COMPONENT, GetLatencyComponentId()));
+  if (l == latency_info.latency_components.end())
+    return;
+
+  rendering_stats_.input_event_count += l->second.event_count;
+  rendering_stats_.total_input_latency +=
+      l->second.event_count *
+      (latency_info.swap_timestamp - l->second.event_time);
+
+  if (CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableGpuBenchmarking))
+    Send(new ViewMsg_SetBrowserRenderingStats(routing_id_, rendering_stats_));
 }
 
 }  // namespace content