Refactoring: Merge VideoSenderConfig and AudioSenderConfig.

media/cast/sender/h264_vt_encoder.h

Index: media/cast/sender/h264_vt_encoder.h
diff --git a/media/cast/sender/h264_vt_encoder.h b/media/cast/sender/h264_vt_encoder.h
index b6dbd9d892a0a32c83532b94d7139aa15da4fd70..2e4c3f0024a769b868de23e2a95fca6e2bb37b29 100644
--- a/media/cast/sender/h264_vt_encoder.h
+++ b/media/cast/sender/h264_vt_encoder.h
@@ -33,11 +33,11 @@ class H264VideoToolboxEncoder : public VideoEncoder,
  public:
   // Returns true if the current platform and system configuration supports
   // using H264VideoToolboxEncoder with the given |video_config|.
-  static bool IsSupported(const VideoSenderConfig& video_config);
+  static bool IsSupported(const FrameSenderConfig& video_config);
 
   H264VideoToolboxEncoder(
       const scoped_refptr<CastEnvironment>& cast_environment,
-      const VideoSenderConfig& video_config,
+      const FrameSenderConfig& video_config,
       const StatusChangeCallback& status_change_cb);
   ~H264VideoToolboxEncoder() final;
 
@@ -92,7 +92,7 @@ class H264VideoToolboxEncoder : public VideoEncoder,
   // VideoSenderConfig copy so we can create compression sessions on demand.
   // This is needed to recover from backgrounding and other events that can
   // invalidate compression sessions.
-  const VideoSenderConfig video_config_;
+  const FrameSenderConfig video_config_;
 
   // Frame size of the current compression session. Can be changed by submitting
   // a frame of a different size, which will cause a compression session reset.