Experiment with more aggressive MSE GC on memory pressure

media/filters/source_buffer_state.cc

 // Copyright 2016 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/source_buffer_state.h"
 
 #include <set>
 
 #include "base/callback_helpers.h"
 #include "base/command_line.h"
@@ skipping 288 matching lines @@
     uint64_t estimated_new_size = newDataSize * curr_size / total_buffered_size;
     DCHECK_LE(estimated_new_size, SIZE_MAX);
     success &= it.second->EvictCodedFrames(
         media_time, static_cast<size_t>(estimated_new_size));
   }
 
   DVLOG(3) << __func__ << " success=" << success;
   return success;
 }
 
+void SourceBufferState::OnMemoryPressure(
+    DecodeTimestamp media_time,
+    base::MemoryPressureListener::MemoryPressureLevel memory_pressure_level,
+    bool force_instant_gc) {
+  // Notify video streams about memory pressure first, since video typically
+  // takes up the most memory and that's where we can expect most savings.
+  for (const auto& it : video_streams_) {
+    it.second->OnMemoryPressure(media_time, memory_pressure_level,
+                                force_instant_gc);
+  }
+  for (const auto& it : audio_streams_) {
+    it.second->OnMemoryPressure(media_time, memory_pressure_level,
+                                force_instant_gc);
+  }
+  for (const auto& it : text_streams_) {
+    it.second->OnMemoryPressure(media_time, memory_pressure_level,
+                                force_instant_gc);
+  }
+}
+
 Ranges<TimeDelta> SourceBufferState::GetBufferedRanges(TimeDelta duration,
                                                        bool ended) const {
   RangesList ranges_list;
   for (const auto& it : audio_streams_)
     ranges_list.push_back(it.second->GetBufferedRanges(duration));
 
   for (const auto& it : video_streams_)
     ranges_list.push_back(it.second->GetBufferedRanges(duration));
 
   for (const auto& it : text_streams_)
@@ skipping 569 matching lines @@
 }
 void SourceBufferState::OnSourceInitDone(
     const StreamParser::InitParameters& params) {
   DCHECK_EQ(state_, PENDING_PARSER_INIT);
   state_ = PARSER_INITIALIZED;
   auto_update_timestamp_offset_ = params.auto_update_timestamp_offset;
   base::ResetAndReturn(&init_cb_).Run(params);
 }
 
 }  // namespace media