Enable splice frames and partial appends for AAC; with test!

media/filters/chunk_demuxer.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/filters/chunk_demuxer.h"
 
 #include <algorithm>
 #include <limits>
 #include <list>
 
@@ skipping 826 matching lines @@
 
 bool ChunkDemuxerStream::UpdateAudioConfig(const AudioDecoderConfig& config,
                                            const LogCB& log_cb) {
   DCHECK(config.IsValidConfig());
   DCHECK_EQ(type_, AUDIO);
   base::AutoLock auto_lock(lock_);
   if (!stream_) {
     DCHECK_EQ(state_, UNINITIALIZED);
 
     // On platforms which support splice frames, enable splice frames and
-    // partial append window support for a limited set of codecs.
-    // TODO(dalecurtis): Verify this works for codecs other than MP3 and Vorbis.
-    // Right now we want to be extremely conservative to ensure we don't break
-    // the world.
-    const bool mp3_or_vorbis =
-        config.codec() == kCodecMP3 || config.codec() == kCodecVorbis;
-    splice_frames_enabled_ = splice_frames_enabled_ && mp3_or_vorbis;
+    // partial append window support for most codecs (notably: not opus).
+    const bool codec_supported = config.codec() == kCodecMP3 ||
+                                 config.codec() == kCodecAAC ||
+                                 config.codec() == kCodecVorbis;
+    splice_frames_enabled_ = splice_frames_enabled_ && codec_supported;
     partial_append_window_trimming_enabled_ =
-        splice_frames_enabled_ && mp3_or_vorbis;
+        splice_frames_enabled_ && codec_supported;
 
     stream_.reset(
         new SourceBufferStream(config, log_cb, splice_frames_enabled_));
     return true;
   }
 
   return stream_->UpdateAudioConfig(config);
 }
 
 bool ChunkDemuxerStream::UpdateVideoConfig(const VideoDecoderConfig& config,
@@ skipping 836 matching lines @@
 }
 
 void ChunkDemuxer::ShutdownAllStreams() {
   for (SourceStateMap::iterator itr = source_state_map_.begin();
        itr != source_state_map_.end(); ++itr) {
     itr->second->Shutdown();
   }
 }
 
 }  // namespace media