Fix mime type mappings when the unified media pipeline is enabled.

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 0746e713f20785915aada189dc328dcd5bdd1aa2..4ae15b9cd389cec9c4f2b58e9357c949305c3959 100644
--- a/content/renderer/render_thread_impl.cc
+++ b/content/renderer/render_thread_impl.cc
@@ -809,6 +809,11 @@ void RenderThreadImpl::Init() {
   // been initialized by the Zygote before this instance became a Renderer.
   media::InitializeMediaLibrary();
 
+#if defined(OS_ANDROID)
+  if (!command_line.HasSwitch(switches::kDisableAcceleratedVideoDecode))
+    media::EnablePlatformDecoderSupport();
+#endif
+
   memory_pressure_listener_.reset(new base::MemoryPressureListener(
       base::Bind(&RenderThreadImpl::OnMemoryPressure, base::Unretained(this))));