gpu: Use GpuMemoryBufferManager from GpuService when possible.

content/browser/gpu/browser_gpu_channel_host_factory.cc

Index: content/browser/gpu/browser_gpu_channel_host_factory.cc
diff --git a/content/browser/gpu/browser_gpu_channel_host_factory.cc b/content/browser/gpu/browser_gpu_channel_host_factory.cc
index 345ad2a4f423957b4e60b9751365084ef4b0a464..f6af12a0dfad395b19ed828e26238b9453d2be36 100644
--- a/content/browser/gpu/browser_gpu_channel_host_factory.cc
+++ b/content/browser/gpu/browser_gpu_channel_host_factory.cc
@@ -312,6 +312,11 @@ BrowserGpuChannelHostFactory::EstablishGpuChannelSync() {
   return gpu_channel_;
 }
 
+gpu::GpuMemoryBufferManager*
+BrowserGpuChannelHostFactory::GetGpuMemoryBufferManager() {
+  return gpu_memory_buffer_manager_.get();
+}
+
 gpu::GpuChannelHost* BrowserGpuChannelHostFactory::GetGpuChannel() {
   if (gpu_channel_.get() && !gpu_channel_->IsLost())
     return gpu_channel_.get();