Make RendererGpuVideoDecoderFactories live on arbitrary threads.

content/renderer/media/media_stream_dependency_factory.cc

Index: content/renderer/media/media_stream_dependency_factory.cc
diff --git a/content/renderer/media/media_stream_dependency_factory.cc b/content/renderer/media/media_stream_dependency_factory.cc
index f15f1036fbd1830f86fdd17e2544e55cc306aff6..82e72ae4760d2eec293205dab8a4eef2ad6f3052 100644
--- a/content/renderer/media/media_stream_dependency_factory.cc
+++ b/content/renderer/media/media_stream_dependency_factory.cc
@@ -225,7 +225,8 @@ class SourceStateObserver : public webrtc::ObserverInterface,
 
 MediaStreamDependencyFactory::MediaStreamDependencyFactory(
     VideoCaptureImplManager* vc_manager,
-    P2PSocketDispatcher* p2p_socket_dispatcher)
+    P2PSocketDispatcher* p2p_socket_dispatcher,
+    const scoped_refptr<base::MessageLoopProxy>& media_loop_proxy)
     : network_manager_(NULL),
 #if defined(GOOGLE_TV)
       decoder_factory_tv_(NULL),
@@ -234,7 +235,8 @@ MediaStreamDependencyFactory::MediaStreamDependencyFactory(
       p2p_socket_dispatcher_(p2p_socket_dispatcher),
       signaling_thread_(NULL),
       worker_thread_(NULL),
-      chrome_worker_thread_("Chrome_libJingle_WorkerThread") {
+      chrome_worker_thread_("Chrome_libJingle_WorkerThread"),
+      media_loop_proxy_(media_loop_proxy) {
 }
 
 MediaStreamDependencyFactory::~MediaStreamDependencyFactory() {
@@ -497,10 +499,12 @@ bool MediaStreamDependencyFactory::CreatePeerConnectionFactory() {
 
     const CommandLine* cmd_line = CommandLine::ForCurrentProcess();
     if (cmd_line->HasSwitch(switches::kEnableWebRtcHWDecoding)) {
-      scoped_refptr<media::GpuVideoDecoder::Factories> gpu_factories =
-          RenderThreadImpl::current()->GetGpuFactories();
-      if (gpu_factories.get() != NULL)
-        decoder_factory.reset(new RTCVideoDecoderFactory(gpu_factories));
+      scoped_refptr<content::RendererGpuVideoDecoderFactories> gpu_factories =
+          RenderThreadImpl::current()->GetGpuFactories(media_loop_proxy_);

[scherkus (not reviewing), 2013/07/19 18:13:58]

how about replacing media_loop_proxy_ with a call to
RenderThreadImpl::current()->GetMediaThreadMessageLoopProxy() ?

[wuchengli, 2013/07/20 06:04:14]

Good idea. Done.

+      if (gpu_factories.get() != NULL) {
+        decoder_factory.reset(
+            new RTCVideoDecoderFactory(media_loop_proxy_, gpu_factories));
+      }
     }
 #if defined(GOOGLE_TV)
     // PeerConnectionFactory will hold the ownership of this