Add support for partial append window end trimming.

media/filters/frame_processor.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 MEDIA_FILTERS_FRAME_PROCESSOR_H_
 #define MEDIA_FILTERS_FRAME_PROCESSOR_H_
 
 #include <map>
 
 #include "base/basictypes.h"
@@ skipping 96 matching lines @@
   bool FlushProcessedFrames();
 
   // Handles partial append window trimming of |buffer|.  Returns true if the
   // given |buffer| can be partially trimmed or have preroll added; otherwise,
   // returns false.
   //
   // If |buffer| overlaps |append_window_start|, the portion of |buffer| before
   // |append_window_start| will be marked for post-decode discard.  Further, if
   // |audio_preroll_buffer_| exists and abuts |buffer|, it will be set as
   // preroll on |buffer| and |audio_preroll_buffer_| will be cleared.  If the
-  // preroll buffer does not abut |buffer|, it will be discarded, but not used.
+  // preroll buffer does not abut |buffer|, it will be discarded unused.
+  //
+  // Likewise, if |buffer| overlaps |append_window_end|, the portion of |buffer|
+  // after |append_window_end| will be marked for post-decode discard.
   //
   // If |buffer| lies entirely before |append_window_start|, and thus would
   // normally be discarded, |audio_preroll_buffer_| will be set to |buffer| and
   // the method will return false.
   bool HandlePartialAppendWindowTrimming(
       base::TimeDelta append_window_start,
       base::TimeDelta append_window_end,
       const scoped_refptr<StreamParserBuffer>& buffer);
 
   // Helper that processes one frame with the coded frame processing algorithm.
@@ skipping 33 matching lines @@
   base::TimeDelta group_end_timestamp_;
 
   UpdateDurationCB update_duration_cb_;
 
   DISALLOW_COPY_AND_ASSIGN(FrameProcessor);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_FILTERS_FRAME_PROCESSOR_H_