Make RendererGpuVideoDecoderFactories live on arbitrary threads.

content/renderer/render_thread_impl.cc

Index: content/renderer/render_thread_impl.cc
diff --git a/content/renderer/render_thread_impl.cc b/content/renderer/render_thread_impl.cc
index 31cb7bb3e5bb3b57ec149b16544b50d57537a0be..fa42e78815573fa519a126414455db1ad6808c92 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -69,7 +69,6 @@
 #include "content/renderer/media/media_stream_dependency_factory.h"
 #include "content/renderer/media/midi_message_filter.h"
 #include "content/renderer/media/peer_connection_tracker.h"
-#include "content/renderer/media/renderer_gpu_video_decoder_factories.h"
 #include "content/renderer/media/video_capture_impl_manager.h"
 #include "content/renderer/media/video_capture_message_filter.h"
 #include "content/renderer/memory_benchmarking_extension.h"
@@ -887,7 +886,8 @@ void RenderThreadImpl::PostponeIdleNotification() {
 }
 
 scoped_refptr<media::GpuVideoDecoder::Factories>
-RenderThreadImpl::GetGpuFactories() {
+RenderThreadImpl::GetGpuFactories(
+    const scoped_refptr<base::MessageLoopProxy>& factories_loop) {
   DCHECK(IsMainThread());
 
   const CommandLine* cmd_line = CommandLine::ForCurrentProcess();
@@ -896,10 +896,6 @@ RenderThreadImpl::GetGpuFactories() {
   if (!cmd_line->HasSwitch(switches::kDisableAcceleratedVideoDecode))
     context3d = GetGpuVDAContext3D();
   if (context3d) {
-    scoped_refptr<base::MessageLoopProxy> factories_loop =
-        compositor_message_loop_proxy();
-    if (!factories_loop.get())
-      factories_loop = base::MessageLoopProxy::current();
     GpuChannelHost* gpu_channel_host = GetGpuChannel();
     if (gpu_channel_host) {
       gpu_factories = new RendererGpuVideoDecoderFactories(