Code:    AudioSystemImplTest()
      : use_audio_thread_(GetParam()), audio_thread_("AudioSystemThread") {
     if (use_audio_thread_) {
       audio_thread_.StartAndWaitForTesting();
       audio_manager_.reset(
          new media::MockAudioManager(audio_thread_.task_runner()));
    } else {
       audio_manager_.reset(new media::MockAudioManager(
           base::ThreadTaskRunnerHandle::Get().get()));
     }
    audio_manager_->SetInputStreamParameters(
        media::AudioParameters::UnavailableDeviceParams());
     audio_system_ = media::AudioSystemImpl::Create(audio_manager_.get());
     EXPECT_EQ(AudioSystem::Get(), audio_system_.get());
   }

Vulnerability Type: DoS 
CWE ID: 
Summary: Multiple unspecified vulnerabilities in Google Chrome before 43.0.2357.65 allow attackers to cause a denial of service or possibly have other impact via unknown vectors.
Commit Message: Switching AudioOutputAuthorizationHandler from using AudioManager interface to AudioSystem one.

BUG=672468
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel

Review-Url: https://codereview.chromium.org/2692203003
Cr-Commit-Position: refs/heads/master@{#450939}