Add return-by-value implementations of blink::WebMediaPlayer::buffered()

content/renderer/media/buffered_data_source_host_impl.h

 // Copyright 2014 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 CONTENT_RENDERER_MEDIA_BUFFERED_DATA_SOURCE_HOST_IMPL_H_
 #define CONTENT_RENDERER_MEDIA_BUFFERED_DATA_SOURCE_HOST_IMPL_H_
 
 #include "base/time/time.h"
 #include "content/common/content_export.h"
 #include "content/renderer/media/buffered_data_source.h"
 #include "media/base/ranges.h"
 
 namespace content {
 
 // Provides an implementation of BufferedDataSourceHost that translates the
 // buffered byte ranges into estimated time ranges.
 class CONTENT_EXPORT BufferedDataSourceHostImpl
     : public BufferedDataSourceHost {
  public:
   BufferedDataSourceHostImpl();
   virtual ~BufferedDataSourceHostImpl();
 
   // BufferedDataSourceHost implementation.
   virtual void SetTotalBytes(int64 total_bytes) OVERRIDE;
   virtual void AddBufferedByteRange(int64 start, int64 end) OVERRIDE;
 
   // Translate the byte ranges to time ranges and append them to the list.
+  // TODO(sandersd): This is a confusing name, find something better.
   void AddBufferedTimeRanges(
       media::Ranges<base::TimeDelta>* buffered_time_ranges,
-      base::TimeDelta media_duration);
+      base::TimeDelta media_duration) const;
 
   bool DidLoadingProgress();
 
  private:
   // Total size of the data source.
   int64 total_bytes_;
 
   // List of buffered byte ranges for estimating buffered time.
   media::Ranges<int64> buffered_byte_ranges_;
 
   // True when AddBufferedByteRange() has been called more recently than
   // DidLoadingProgress().
   bool did_loading_progress_;
 
   DISALLOW_COPY_AND_ASSIGN(BufferedDataSourceHostImpl);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_RENDERER_MEDIA_BUFFERED_DATA_SOURCE_HOST_IMPL_H_