Checking RendererThreadImpl for null when creating media player.

content/renderer/media/audio_device_factory.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 "content/renderer/media/audio_device_factory.h"
 
 #include <algorithm>
 
 #include "base/logging.h"
 #include "base/metrics/histogram_macros.h"
@@ skipping 54 matching lines @@
   return base::FeatureList::IsEnabled(media::kNewAudioRenderingMixingStrategy);
 }
 
 scoped_refptr<media::SwitchableAudioRendererSink> NewMixableSink(
     AudioDeviceFactory::SourceType source_type,
     int render_frame_id,
     int session_id,
     const std::string& device_id,
     const url::Origin& security_origin) {
   RenderThreadImpl* render_thread = RenderThreadImpl::current();
+  DCHECK(render_thread) << "RenderThreadImpl is not instantiated, or "
+                        << "GetOutputDeviceInfo() is called on a wrong thread ";
   return scoped_refptr<media::AudioRendererMixerInput>(
       render_thread->GetAudioRendererMixerManager()->CreateInput(
           render_frame_id, session_id, device_id, security_origin,
           AudioDeviceFactory::GetSourceLatencyType(source_type)));
 }
 
 }  // namespace
 
 media::AudioLatency::LatencyType AudioDeviceFactory::GetSourceLatencyType(
     AudioDeviceFactory::SourceType source) {
@@ skipping 128 matching lines @@
                                                device_id, security_origin);
     if (sink)
       return sink;
   }
 
   return NewOutputDevice(render_frame_id, session_id, device_id,
                          security_origin);
 }
 
 }  // namespace content