Add support for latency measurement to Telemetry smoothness benchmarks.

content/common/browser_rendering_stats.h

+// Copyright (c) 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_COMMON_BROWSER_RENDERING_STATS_H_
+#define CONTENT_COMMON_BROWSER_RENDERING_STATS_H_
+
+#include "base/time.h"
+#include "cc/debug/rendering_stats.h"
+#include "content/common/content_export.h"
+
+namespace content {
+
+struct CONTENT_EXPORT BrowserRenderingStats {
+  BrowserRenderingStats();
+  ~BrowserRenderingStats();
+
+  uint32 input_event_count;
+  base::TimeDelta total_input_latency;
+
+  // Note: when adding new members, please remember to update enumerateFields
+  // in browser_rendering_stats.cc.
+
+  // Outputs the fields in this structure to the provided enumerator.
+  void EnumerateFields(cc::RenderingStats::Enumerator* enumerator) const;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_BROWSER_RENDERING_STATS_H_