Collapse AudioRendererMixer and OnMoreDataResampler into AudioTransform.

media/base/audio_pull_fifo.cc

Index: media/base/audio_pull_fifo.cc
diff --git a/media/base/audio_pull_fifo.cc b/media/base/audio_pull_fifo.cc
index b1622e0c4110740605d1dd81a5ce8f11f0999aef..584f8cb7ad5adff33c7ed9ede7438c005f5b04d1 100644
--- a/media/base/audio_pull_fifo.cc
+++ b/media/base/audio_pull_fifo.cc
@@ -11,7 +11,8 @@
 namespace media {
 
 AudioPullFifo::AudioPullFifo(int channels, int frames, const ReadCB& read_cb)
-    : read_cb_(read_cb) {
+    : read_cb_(read_cb),
+      output_frames_ready_(0) {
   fifo_.reset(new AudioFifo(channels, frames));
   bus_ = AudioBus::Create(channels, frames);
 }
@@ -32,6 +33,8 @@ void AudioPullFifo::Consume(AudioBus* destination, int frames_to_consume) {
 
   // Get the remaining audio frames from the producer using the callback.
   while (remaining_frames_to_provide > 0) {
+    output_frames_ready_ = write_pos;

[scherkus (not reviewing), 2012/11/14 22:43:50]

do we need to update output_frames_ready_ anywhere else? e.g., Clear()?

[DaleCurtis, 2012/11/15 00:30:59]

No, it's not valid to call Clear() during Consume(), the class is not thread
safe.

I'm thinking it might be better to provide this value to the callback directly
instead of this weird side-channel value which is only valid at certain times.
There are only two users (opus and AudioTransform), so it shouldn't be a hard
change.

+
     // Fill up the FIFO by acquiring audio data from the producer.
     read_cb_.Run(bus_.get());
     fifo_->Push(bus_.get());