Split the media context from the compositor worker context.

content/renderer/render_thread_impl.h

Index: content/renderer/render_thread_impl.h
diff --git a/content/renderer/render_thread_impl.h b/content/renderer/render_thread_impl.h
index 806d32bfbd261725bf64de15bf2db7ae1358d6c4..e6306789cc868a11a94a1a17082826e7dd474b4f 100644
--- a/content/renderer/render_thread_impl.h
+++ b/content/renderer/render_thread_impl.h
@@ -339,8 +339,10 @@ class CONTENT_EXPORT RenderThreadImpl
   // A TaskRunner instance that runs tasks on the raster worker pool.
   base::TaskRunner* GetWorkerTaskRunner();
 
-  // Returns a shared worker context provider that can be used on any thread.
-  scoped_refptr<ContextProviderCommandBuffer> SharedWorkerContextProvider();
+  // Returns a worker context provider that will be bound on the compositor
+  // thread.
+  scoped_refptr<ContextProviderCommandBuffer>
+  SharedCompositorWorkerContextProvider();
 
   // Causes the idle handler to skip sending idle notifications
   // on the two next scheduled calls, so idle notifications are