Report user actions when gesture starts and stops in user_model.

content/renderer/render_thread_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_RENDERER_RENDER_THREAD_IMPL_H_
 #define CONTENT_RENDERER_RENDER_THREAD_IMPL_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <set>
 #include <string>
 #include <vector>
 
 #include "base/cancelable_callback.h"
 #include "base/macros.h"
 #include "base/memory/memory_pressure_listener.h"
 #include "base/memory/ref_counted.h"
+#include "base/metrics/user_metrics.h"
 #include "base/metrics/user_metrics_action.h"
 #include "base/observer_list.h"
 #include "base/strings/string16.h"
 #include "base/threading/thread_checker.h"
 #include "base/timer/timer.h"
 #include "build/build_config.h"
 #include "content/child/child_thread_impl.h"
 #include "content/common/content_export.h"
 #include "content/common/frame_replication_state.h"
 #include "content/common/gpu/client/gpu_channel_host.h"
@@ skipping 665 matching lines @@
 
     int routing_id_;
     mojo::shell::mojom::InterfaceProviderRequest services_;
     mojo::shell::mojom::InterfaceProviderPtr exposed_services_;
   };
 
   typedef std::map<int, scoped_refptr<PendingRenderFrameConnect>>
       PendingRenderFrameConnectMap;
   PendingRenderFrameConnectMap pending_render_frame_connects_;
 
+  // Callback for logging UMA user action.
+  base::ActionCallback action_callback_;
+
   DISALLOW_COPY_AND_ASSIGN(RenderThreadImpl);
 };
 
 #if defined(COMPILER_MSVC)
 #pragma warning(pop)
 #endif
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_RENDER_THREAD_IMPL_H_