Add callback in VideoDecoder and AudioDecoder to return decoded frames.

media/filters/vpx_video_decoder.cc

Index: media/filters/vpx_video_decoder.cc
diff --git a/media/filters/vpx_video_decoder.cc b/media/filters/vpx_video_decoder.cc
index 23a90b2f1c2b4f4d2cd87c27329b5ddbe185c21d..bf3b172c98fe8f2940909bddbda2245cc7764922 100644
--- a/media/filters/vpx_video_decoder.cc
+++ b/media/filters/vpx_video_decoder.cc
@@ -215,7 +215,8 @@ VpxVideoDecoder::~VpxVideoDecoder() {
 
 void VpxVideoDecoder::Initialize(const VideoDecoderConfig& config,
                                  bool low_delay,
-                                 const PipelineStatusCB& status_cb) {
+                                 const PipelineStatusCB& status_cb,
+                                 const OutputCB& output_cb) {
   DCHECK(task_runner_->BelongsToCurrentThread());
   DCHECK(config.IsValidConfig());
   DCHECK(!config.is_encrypted());
@@ -229,6 +230,7 @@ void VpxVideoDecoder::Initialize(const VideoDecoderConfig& config,
   // Success!
   config_ = config;
   state_ = kNormal;
+  output_cb_ = output_cb;

[xhwang, 2014/06/07 00:35:15]

Do we need BindToCurrentLoop() here? Please check all AudioDecoder/VideoDecoder
impls to make sure we have consistent behavior.

[Sergey Ulanov, 2014/06/07 01:12:09]

Yes. Done.

   status_cb.Run(PIPELINE_OK);
 }
 
@@ -314,13 +316,13 @@ void VpxVideoDecoder::Decode(const scoped_refptr<DecoderBuffer>& buffer,
   decode_cb_ = BindToCurrentLoop(decode_cb);
 
   if (state_ == kError) {
-    base::ResetAndReturn(&decode_cb_).Run(kDecodeError, NULL);
+    base::ResetAndReturn(&decode_cb_).Run(kDecodeError);
     return;
   }
 
   // Return empty frames if decoding has finished.
   if (state_ == kDecodeFinished) {
-    base::ResetAndReturn(&decode_cb_).Run(kOk, VideoFrame::CreateEOSFrame());
+    base::ResetAndReturn(&decode_cb_).Run(kOk);
     return;
   }
 
@@ -352,24 +354,22 @@ void VpxVideoDecoder::DecodeBuffer(const scoped_refptr<DecoderBuffer>& buffer) {
   // Transition to kDecodeFinished on the first end of stream buffer.
   if (state_ == kNormal && buffer->end_of_stream()) {
     state_ = kDecodeFinished;
-    base::ResetAndReturn(&decode_cb_).Run(kOk, VideoFrame::CreateEOSFrame());
+    output_cb_.Run(VideoFrame::CreateEOSFrame());
+    base::ResetAndReturn(&decode_cb_).Run(kOk);
     return;
   }
 
   scoped_refptr<VideoFrame> video_frame;
   if (!VpxDecode(buffer, &video_frame)) {
     state_ = kError;
-    base::ResetAndReturn(&decode_cb_).Run(kDecodeError, NULL);
+    base::ResetAndReturn(&decode_cb_).Run(kDecodeError);
     return;
   }
 
-  // If we didn't get a frame we need more data.
-  if (!video_frame.get()) {
-    base::ResetAndReturn(&decode_cb_).Run(kNotEnoughData, NULL);
-    return;
-  }
+  base::ResetAndReturn(&decode_cb_).Run(kOk);
 
-  base::ResetAndReturn(&decode_cb_).Run(kOk, video_frame);
+  if (video_frame)
+    output_cb_.Run(video_frame);
 }
 
 bool VpxVideoDecoder::VpxDecode(const scoped_refptr<DecoderBuffer>& buffer,