Fixing deadlock by removing unnesessary lock in AudioRendererMixer

media/base/audio_renderer_mixer.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/base/audio_renderer_mixer.h"
 
 #include <cmath>
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
@@ skipping 97 matching lines @@
       return;
     }
   }
 
   // An error callback should always exist when called.
   NOTREACHED();
 }
 
 OutputDeviceInfo AudioRendererMixer::GetOutputDeviceInfo() {
   DVLOG(1) << __FUNCTION__;
-  base::AutoLock auto_lock(lock_);
   return audio_sink_->GetOutputDeviceInfo();
 }
 
 int AudioRendererMixer::Render(AudioBus* audio_bus,
                                uint32_t frames_delayed,
                                uint32_t frames_skipped) {
   base::AutoLock auto_lock(lock_);
 
   // If there are no mixer inputs and we haven't seen one for a while, pause the
   // sink to avoid wasting resources when media elements are present but remain
@@ skipping 11 matching lines @@
 }
 
 void AudioRendererMixer::OnRenderError() {
   // Call each mixer input and signal an error.
   base::AutoLock auto_lock(lock_);
   for (const auto& cb : error_callbacks_)
     cb.Run();
 }
 
 }  // namespace media