gpu: Introduce GpuChannelEstablishFactory.

content/browser/gpu/browser_gpu_channel_host_factory.h

Index: content/browser/gpu/browser_gpu_channel_host_factory.h
diff --git a/content/browser/gpu/browser_gpu_channel_host_factory.h b/content/browser/gpu/browser_gpu_channel_host_factory.h
index d0692ae5299bb43002f1dc721369d7a561c6a730..ba9a956ef04b45f915413f9a5aeaefd625eeed2d 100644
--- a/content/browser/gpu/browser_gpu_channel_host_factory.h
+++ b/content/browser/gpu/browser_gpu_channel_host_factory.h
@@ -42,7 +42,7 @@ class CONTENT_EXPORT BrowserGpuChannelHostFactory
       CauseForGpuLaunch cause_for_gpu_launch);
 #endif
   void EstablishGpuChannel(CauseForGpuLaunch cause_for_gpu_launch,
-                           const base::Closure& callback);
+                           const gpu::GpuChannelEstablishedCallback& callback);
   gpu::GpuChannelHost* GetGpuChannel();
   int GetGpuChannelId() { return gpu_client_id_; }
 
@@ -70,7 +70,7 @@ class CONTENT_EXPORT BrowserGpuChannelHostFactory
   std::unique_ptr<BrowserGpuMemoryBufferManager> gpu_memory_buffer_manager_;
   int gpu_host_id_;
   scoped_refptr<EstablishRequest> pending_request_;
-  std::vector<base::Closure> established_callbacks_;
+  std::vector<gpu::GpuChannelEstablishedCallback> established_callbacks_;
 
   static BrowserGpuChannelHostFactory* instance_;