Change audio render thread checking to use new AudioRendererSink::BelongsToRendererThread()

media/base/audio_renderer_mixer_input.h

Index: media/base/audio_renderer_mixer_input.h
diff --git a/media/base/audio_renderer_mixer_input.h b/media/base/audio_renderer_mixer_input.h
index 042fe06575dd21b5ee618a1b959290f4766355ae..272308ab1c31b2c565406c1f11f192596a71e321 100644
--- a/media/base/audio_renderer_mixer_input.h
+++ b/media/base/audio_renderer_mixer_input.h
@@ -51,6 +51,7 @@ class MEDIA_EXPORT AudioRendererMixerInput
   void SwitchOutputDevice(const std::string& device_id,
                           const url::Origin& security_origin,
                           const OutputDeviceStatusCB& callback) override;
+  bool BelongsToRenderingThread() override;
 
   // Called by AudioRendererMixer when an error occurs.
   void OnRenderError();