Introducing DecoderBuffer and general Buffer cleanup.

media/base/buffers.cc

 // 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.
 
 #include "media/base/buffers.h"
 
 namespace media {
 
 Buffer::Buffer(base::TimeDelta timestamp, base::TimeDelta duration)
     : timestamp_(timestamp),
       duration_(duration) {
 }
 
 Buffer::~Buffer() {}
 
 bool Buffer::IsEndOfStream() const {
   return GetData() == NULL;
 }
 
-const DecryptConfig* Buffer::GetDecryptConfig() const {
-  return NULL;
-}
-
 }  // namespace media