No EOS frame in {Audio|Video}Decoder::OutputCB.

media/base/audio_decoder.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef MEDIA_BASE_AUDIO_DECODER_H_
 #define MEDIA_BASE_AUDIO_DECODER_H_
 
 #include "base/callback.h"
 #include "base/memory/ref_counted.h"
 #include "media/base/audio_decoder_config.h"
@@ skipping 12 matching lines @@
   // Status codes for decode operations.
   // TODO(rileya): Now that both AudioDecoder and VideoDecoder Status enums
   // match, break them into a decoder_status.h.
   enum Status {
     kOk,  // We're all good.
     kAborted,  // We aborted as a result of Stop() or Reset().
     kDecodeError,  // A decoding error occurred.
     kDecryptError  // Decrypting error happened.
   };
 
-  // Callback to return decoded buffers.
+  // Callback for AudioDecoder to return a decoded frame whenever it becomes
+  // available. Only non-EOS frames should be returned via this callback.
   typedef base::Callback<void(const scoped_refptr<AudioBuffer>&)> OutputCB;
 
   // Callback for Decode(). Called after the decoder has completed decoding
   // corresponding DecoderBuffer, indicating that it's ready to accept another
   // buffer to decode.
   typedef base::Callback<void(Status)> DecodeCB;
 
   AudioDecoder();
   virtual ~AudioDecoder();
 
@@ skipping 31 matching lines @@
   // must be called before destructing the decoder.
   virtual void Stop() = 0;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AudioDecoder);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_BASE_AUDIO_DECODER_H_