Introduce AudioRendererSink::IsOptimizedForHardwareParameters

media/base/audio_renderer_sink.h

Index: media/base/audio_renderer_sink.h
diff --git a/media/base/audio_renderer_sink.h b/media/base/audio_renderer_sink.h
index 4052112bab555b6703c90962422323f5cbeff0e4..b6edaaa967bfe33d5e168f7cf71f286bc0d01c29 100644
--- a/media/base/audio_renderer_sink.h
+++ b/media/base/audio_renderer_sink.h
@@ -66,12 +66,15 @@ class AudioRendererSink
   // Returns |true| on success.
   virtual bool SetVolume(double volume) = 0;
 
-  // Returns current output device information. If the information is not
+  // Returns current output device id and status with the optimal parameters
+  // given the sink's internal state. These may be the output device's
+  // parameters or the given |preferred_params|. If the information is not
   // available yet, this method may block until it becomes available.
   // If the sink is not associated with any output device, |device_status| of
   // OutputDeviceInfo should be set to OUTPUT_DEVICE_STATUS_ERROR_INTERNAL.
   // Must never be called on the IO thread.
-  virtual OutputDeviceInfo GetOutputDeviceInfo() = 0;
+  virtual OutputDeviceInfo GetOutputDeviceInfo(
+      const AudioParameters& preferred_params = AudioParameters()) = 0;

[o1ka, 2017/04/28 09:57:18]

What happens in the default case?
What if |preferred_params| are not default AudioParameters(), but invalid?

 
   // If DCHECKs are enabled, this function returns true if called on rendering
   // thread, otherwise false. With DCHECKs disabled, it returns true. Thus, it