Make field trials activated in the GPU process be reflected in browser.

content/gpu/gpu_child_thread.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_GPU_GPU_CHILD_THREAD_H_
 #define CONTENT_GPU_GPU_CHILD_THREAD_H_
 
 #include <stdint.h>
 
 #include <memory>
 #include <queue>
 #include <string>
 
 #include "base/command_line.h"
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
+#include "base/metrics/field_trial.h"
 #include "base/time/time.h"
 #include "build/build_config.h"
 #include "content/child/child_thread_impl.h"
 #include "content/common/process_control.mojom.h"
 #include "gpu/command_buffer/service/gpu_preferences.h"
 #include "gpu/config/gpu_info.h"
 #include "gpu/ipc/service/gpu_channel.h"
 #include "gpu/ipc/service/gpu_channel_manager.h"
 #include "gpu/ipc/service/gpu_channel_manager_delegate.h"
 #include "gpu/ipc/service/gpu_config.h"
@@ skipping 18 matching lines @@
 namespace content {
 class GpuProcessControlImpl;
 class GpuWatchdogThread;
 struct EstablishChannelParams;
 
 // The main thread of the GPU child process. There will only ever be one of
 // these per process. It does process initialization and shutdown. It forwards
 // IPC messages to gpu::GpuChannelManager, which is responsible for issuing
 // rendering commands to the GPU.
 class GpuChildThread : public ChildThreadImpl,
-                       public gpu::GpuChannelManagerDelegate {
+                       public gpu::GpuChannelManagerDelegate,
+                       public base::FieldTrialList::Observer {
  public:
   typedef std::queue<IPC::Message*> DeferredMessages;
 
   // Returns the one gpu thread for this process. Note that this can only
   // be accessed when running on the gpu thread itself.
   static GpuChildThread* current();
 
   GpuChildThread(GpuWatchdogThread* gpu_watchdog_thread,
                  bool dead_on_arrival,
                  const gpu::GPUInfo& gpu_info,
                  const DeferredMessages& deferred_messages,
                  gpu::GpuMemoryBufferFactory* gpu_memory_buffer_factory);
 
   GpuChildThread(const gpu::GpuPreferences& gpu_preferences,
                  const InProcessChildThreadParams& params,
                  gpu::GpuMemoryBufferFactory* gpu_memory_buffer_factory);
 
   ~GpuChildThread() override;
 
   void Shutdown() override;
 
   void Init(const base::Time& process_start_time);
   void StopWatchdog();
 
   gpu::GpuPreferences gpu_preferences() { return gpu_preferences_; }
 
  private:
-  // ChildThread overrides.
+  // ChildThreadImpl:.
   bool Send(IPC::Message* msg) override;
   bool OnControlMessageReceived(const IPC::Message& msg) override;
   bool OnMessageReceived(const IPC::Message& msg) override;
 
-  // gpu::GpuChannelManagerDelegate implementation.
+  // gpu::GpuChannelManagerDelegate:
   void SetActiveURL(const GURL& url) override;
   void DidCreateOffscreenContext(const GURL& active_url) override;
   void DidDestroyChannel(int client_id) override;
   void DidDestroyOffscreenContext(const GURL& active_url) override;
   void DidLoseContext(bool offscreen,
                       gpu::error::ContextLostReason reason,
                       const GURL& active_url) override;
   void GpuMemoryUmaStats(const gpu::GPUMemoryUmaStats& params) override;
 #if defined(OS_WIN)
   void SendAcceleratedSurfaceCreatedChildWindow(
       gpu::SurfaceHandle parent_window,
       gpu::SurfaceHandle child_window) override;
 #endif
   void StoreShaderToDisk(int32_t client_id,
                          const std::string& key,
                          const std::string& shader) override;
 
+  // base::FieldTrialList::Observer:
+  void OnFieldTrialGroupFinalized(const std::string& trial_name,
+                                  const std::string& group_name) override;
+
   // Message handlers.
   void OnInitialize(const gpu::GpuPreferences& gpu_preferences);
   void OnFinalize();
   void OnCollectGraphicsInfo();
   void OnGetVideoMemoryUsageStats();
   void OnSetVideoMemoryWindowCount(uint32_t window_count);
 
   void OnClean();
   void OnCrash();
   void OnHang();
@@ skipping 52 matching lines @@
 
   // Bindings to the mojom::ProcessControl impl.
   mojo::BindingSet<mojom::ProcessControl> process_control_bindings_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuChildThread);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_GPU_GPU_CHILD_THREAD_H_