Fix MSE GC, make it less aggressive, more spec-compliant

media/filters/chunk_demuxer.cc

Index: media/filters/chunk_demuxer.cc
diff --git a/media/filters/chunk_demuxer.cc b/media/filters/chunk_demuxer.cc
index d641ded72c00e74a3fd48b9805c1e5f319cf9efa..7ad4c84a436e2695c55abba43d8a9c76f6fdf2ab 100644
--- a/media/filters/chunk_demuxer.cc
+++ b/media/filters/chunk_demuxer.cc
@@ -133,6 +133,14 @@ class SourceState {
   // ChunkDemuxerStreams managed by this object.
   void Remove(TimeDelta start, TimeDelta end, TimeDelta duration);
 
+  // Attempts to perform garbage collection in SourceBuffers associated with
+  // this ChunkDemuxer. Returns true if garbage collection was successful.
+  // |media_time| parameter should indicate the current playback position.
+  // If it's a valid time value, the garbage collection algorithm will make sure
+  // to preserve unconsumed data buffers in the range between last read position
+  // and the current playback position.
+  bool EvictFrames(DecodeTimestamp media_time);
+
   // Returns true if currently parsing a media segment, or false otherwise.
   bool parsing_media_segment() const { return parsing_media_segment_; }
 
@@ -374,6 +382,23 @@ void SourceState::Remove(TimeDelta start, TimeDelta end, TimeDelta duration) {
   }
 }
 
+bool SourceState::EvictFrames(DecodeTimestamp media_time) {
+  bool success = true;
+
+  if (audio_)
+    success = audio_->EvictFrames(media_time) && success;
+
+  if (video_)
+    success = video_->EvictFrames(media_time) && success;
+
+  for (TextStreamMap::iterator itr = text_stream_map_.begin();
+       itr != text_stream_map_.end(); ++itr) {
+    success = itr->second->EvictFrames(media_time) && success;
+  }
+
+  return success;
+}
+
 Ranges<TimeDelta> SourceState::GetBufferedRanges(TimeDelta duration,
                                                  bool ended) const {
   // TODO(acolwell): When we start allowing disabled tracks we'll need to update
@@ -883,6 +908,11 @@ void ChunkDemuxerStream::Remove(TimeDelta start, TimeDelta end,
   stream_->Remove(start, end, duration);
 }
 
+bool ChunkDemuxerStream::EvictFrames(DecodeTimestamp media_time) {
+  base::AutoLock auto_lock(lock_);
+  return stream_->GarbageCollectIfNeeded(media_time);
+}
+
 void ChunkDemuxerStream::OnSetDuration(TimeDelta duration) {
   base::AutoLock auto_lock(lock_);
   stream_->OnSetDuration(duration);
@@ -1106,6 +1136,7 @@ ChunkDemuxer::ChunkDemuxer(
     const base::Closure& open_cb,
     const EncryptedMediaInitDataCB& encrypted_media_init_data_cb,
     const LogCB& log_cb,
+    const GetMediaTimeCB& get_media_time_cb,
     const scoped_refptr<MediaLog>& media_log,
     bool splice_frames_enabled)
     : state_(WAITING_FOR_INIT),
@@ -1115,6 +1146,7 @@ ChunkDemuxer::ChunkDemuxer(
       encrypted_media_init_data_cb_(encrypted_media_init_data_cb),
       enable_text_(false),
       log_cb_(log_cb),
+      get_media_time_cb_(get_media_time_cb),
       media_log_(media_log),
       duration_(kNoTimestamp()),
       user_specified_duration_(-1),
@@ -1317,6 +1349,23 @@ Ranges<TimeDelta> ChunkDemuxer::GetBufferedRanges(const std::string& id) const {
   return itr->second->GetBufferedRanges(duration_, state_ == ENDED);
 }
 
+bool ChunkDemuxer::EvictFrames() {
+  DecodeTimestamp current_media_time;
+  if (!get_media_time_cb_.is_null()) {
+    current_media_time =
+        DecodeTimestamp::FromPresentationTime(get_media_time_cb_.Run());
+  } else {
+    current_media_time = kNoDecodeTimestamp();
+  }
+
+  bool success = true;
+  for (SourceStateMap::iterator itr = source_state_map_.begin();
+       itr != source_state_map_.end(); ++itr) {
+    success = itr->second->EvictFrames(current_media_time) && success;
+  }
+  return success;
+}
+
 void ChunkDemuxer::AppendData(
     const std::string& id,
     const uint8* data,