Revert of Remove threading from RendererGpuVideoAcceleratorFactories

content/renderer/media/rtc_video_encoder_factory.cc

Index: content/renderer/media/rtc_video_encoder_factory.cc
diff --git a/content/renderer/media/rtc_video_encoder_factory.cc b/content/renderer/media/rtc_video_encoder_factory.cc
index 777d69f83c9a13e43d906e35cde8a53d5479d05f..3ff42728df284a88102c2536f1fcbf3e1cb54331 100644
--- a/content/renderer/media/rtc_video_encoder_factory.cc
+++ b/content/renderer/media/rtc_video_encoder_factory.cc
@@ -5,8 +5,8 @@
 #include "content/renderer/media/rtc_video_encoder_factory.h"
 
 #include "content/common/gpu/client/gpu_video_encode_accelerator_host.h"
+#include "content/renderer/media/renderer_gpu_video_accelerator_factories.h"
 #include "content/renderer/media/rtc_video_encoder.h"
-#include "media/filters/gpu_video_accelerator_factories.h"
 #include "media/video/video_encode_accelerator.h"
 
 namespace content {
@@ -59,7 +59,7 @@
 }  // anonymous namespace
 
 RTCVideoEncoderFactory::RTCVideoEncoderFactory(
-    const scoped_refptr<media::GpuVideoAcceleratorFactories>& gpu_factories)
+    const scoped_refptr<RendererGpuVideoAcceleratorFactories>& gpu_factories)
     : gpu_factories_(gpu_factories) {
   // Query media::VideoEncodeAccelerator (statically) for our supported codecs.
   std::vector<media::VideoEncodeAccelerator::SupportedProfile> profiles =
@@ -84,8 +84,11 @@
   }
   if (!found)
     return NULL;
+  // GpuVideoAcceleratorFactories is not thread safe. It cannot be shared
+  // by different encoders. Since we aren't running on the child thread and
+  // cannot create a new factory, clone one instead.
   return new RTCVideoEncoder(
-      type, WebRTCCodecToVideoCodecProfile(type), gpu_factories_);
+      type, WebRTCCodecToVideoCodecProfile(type), gpu_factories_->Clone());
 }
 
 void RTCVideoEncoderFactory::AddObserver(Observer* observer) {