Adding defensive CHECKs for AudioDecoderConfig crash

media/filters/source_buffer_stream.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/source_buffer_stream.h"
 
 #include <algorithm>
 #include <map>
 #include <sstream>
 #include <string>
@@ skipping 1533 matching lines @@
 
   if (!selected_range_)
     return true;
 
   return selected_range_ == ranges_.back();
 }
 
 const AudioDecoderConfig& SourceBufferStream::GetCurrentAudioDecoderConfig() {
   if (config_change_pending_)
     CompleteConfigChange();
+  // Trying to track down crash. http://crbug.com/715761
+  CHECK(current_config_index_ >= 0 &&
+        static_cast<size_t>(current_config_index_) < audio_configs_.size());
   return audio_configs_[current_config_index_];
 }
 
 const VideoDecoderConfig& SourceBufferStream::GetCurrentVideoDecoderConfig() {
   if (config_change_pending_)
     CompleteConfigChange();
+  // Trying to track down crash. http://crbug.com/715761
+  CHECK(current_config_index_ >= 0 &&
+        static_cast<size_t>(current_config_index_) < video_configs_.size());
   return video_configs_[current_config_index_];
 }
 
 const TextTrackConfig& SourceBufferStream::GetCurrentTextTrackConfig() {
   return text_track_config_;
 }
 
 base::TimeDelta SourceBufferStream::GetMaxInterbufferDistance() const {
   if (max_interbuffer_distance_ == kNoTimestamp)
     return base::TimeDelta::FromMilliseconds(kDefaultBufferDurationInMs);
@@ skipping 210 matching lines @@
 
   if (!have_preroll_buffer)
     return false;
 
   pending_buffer_.swap(*out_buffer);
   pending_buffers_complete_ = false;
   return true;
 }
 
 }  // namespace media