Release GPU resources only after renderer GPU channels are closed.

content/common/gpu/gpu_channel_manager.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_COMMON_GPU_GPU_CHANNEL_MANAGER_H_
 #define CONTENT_COMMON_GPU_GPU_CHANNEL_MANAGER_H_
 
 #include <deque>
 #include <string>
 #include <vector>
@@ skipping 123 matching lines @@
                                 int32 sync_point);
 
   void OnRelinquishResources();
   void OnResourcesRelinquished();
 
   void OnUpdateValueState(int client_id,
                           unsigned int target,
                           const gpu::ValueState& state);
 
   void OnLoseAllContexts();
+  void CheckRelinquishGpuResources();
 
   scoped_refptr<base::MessageLoopProxy> io_message_loop_;
   base::WaitableEvent* shutdown_event_;
 
   // Used to send and receive IPC messages from the browser process.
   MessageRouter* const router_;
 
   // These objects manage channels to individual renderer processes there is
   // one channel for each renderer process that has connected to this GPU
   // process.
   GpuChannelMap gpu_channels_;
   scoped_refptr<gfx::GLShareGroup> share_group_;
   scoped_refptr<gpu::gles2::MailboxManager> mailbox_manager_;
   GpuMemoryManager gpu_memory_manager_;
   GpuEventsDispatcher gpu_devtools_events_dispatcher_;
   GpuWatchdog* watchdog_;
   scoped_refptr<gpu::SyncPointManager> sync_point_manager_;
   scoped_ptr<gpu::gles2::ProgramCache> program_cache_;
   scoped_refptr<gpu::gles2::ShaderTranslatorCache> shader_translator_cache_;
   scoped_refptr<gfx::GLSurface> default_offscreen_surface_;
   scoped_ptr<GpuMemoryBufferFactory> gpu_memory_buffer_factory_;
   IPC::SyncChannel* channel_;
   scoped_refptr<IPC::MessageFilter> filter_;
+  bool relinquish_resources_pending_;
 
   // Member variables should appear before the WeakPtrFactory, to ensure
   // that any WeakPtrs to Controller are invalidated before its members
   // variable's destructors are executed, rendering them invalid.
   base::WeakPtrFactory<GpuChannelManager> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(GpuChannelManager);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_COMMON_GPU_GPU_CHANNEL_MANAGER_H_