Cleanup some audio classes with C++11 shine!

media/base/audio_splicer.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_SPLICER_H_
 #define MEDIA_BASE_AUDIO_SPLICER_H_
 
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 #include "base/time/time.h"
@@ skipping 67 matching lines @@
   scoped_ptr<AudioBus> ExtractCrossfadeFromPreSplice(
       scoped_refptr<AudioBuffer>* crossfade_buffer);
 
   // Crossfades |pre_splice_bus->frames()| frames from
   // |post_splice_sanitizer_|
   // with those from |pre_splice_bus|.  Adds the crossfaded buffer to
   // |output_sanitizer_| along with all buffers in |post_splice_sanitizer_|.
   //
   // |post_splice_sanitizer_| will be empty after this operation.
   void CrossfadePostSplice(scoped_ptr<AudioBus> pre_splice_bus,
-                           scoped_refptr<AudioBuffer> crossfade_buffer);
+                           const scoped_refptr<AudioBuffer>& crossfade_buffer);
 
   // Reset the splice and splice end timestamps.
   void reset_splice_timestamps() {
     splice_timestamp_ = max_splice_end_timestamp_ = kNoTimestamp();
   }
 
   const base::TimeDelta max_crossfade_duration_;
   base::TimeDelta splice_timestamp_;
   base::TimeDelta max_splice_end_timestamp_;
 
@@ skipping 16 matching lines @@
   // Whether all buffers which should go into |pre_splice_sanitizer_| have been
   // received.  If true, buffers should now be put in |post_splice_sanitizer_|.
   bool have_all_pre_splice_buffers_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(AudioSplicer);
 };
 
 }  // namespace media
 
 #endif