Ensures that audio tasks cannot run after AudioManager is deleted.

media/audio/audio_system_impl_unittest.cc

 // Copyright 2017 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/audio/audio_system_impl.h"
 #include "base/memory/ptr_util.h"
 #include "base/run_loop.h"
 #include "base/single_thread_task_runner.h"
 #include "base/task_runner_util.h"
 #include "base/threading/thread.h"
@@ skipping 60 matching lines @@
                    base::Unretained(&input_device_descriptions_)));
     audio_manager_->SetOutputDeviceDescriptionsCallback(
         base::Bind(get_device_descriptions,
                    base::Unretained(&output_device_descriptions_)));
 
     audio_system_ = media::AudioSystemImpl::Create(audio_manager_.get());
     EXPECT_EQ(AudioSystem::Get(), audio_system_.get());
   }
 
   ~AudioSystemImplTest() override {
-    // Deleting |audio_manager_| on its thread.
     audio_system_.reset();
     EXPECT_EQ(AudioSystem::Get(), nullptr);
-    audio_manager_.reset();
-    audio_thread_.Stop();
+
+    audio_manager_->GetTaskRunner()->PostTask(
+        FROM_HERE, base::Bind(&media::AudioManager::Shutdown,
+                              base::Unretained(audio_manager_.get())));
   }
 
   void OnAudioParams(const AudioParameters& expected,
                      const AudioParameters& received) {
     EXPECT_TRUE(thread_checker_.CalledOnValidThread());
     EXPECT_EQ(expected.AsHumanReadableString(),
               received.AsHumanReadableString());
     AudioParametersReceived();
   }
 
@@ skipping 27 matching lines @@
 
   // Mocks to verify that AudioSystem replied with an expected callback.
   MOCK_METHOD0(AudioParametersReceived, void(void));
   MOCK_METHOD1(HasInputDevicesCallback, void(bool));
   MOCK_METHOD0(DeviceDescriptionsReceived, void(void));
 
  protected:
   base::MessageLoop message_loop_;
   base::ThreadChecker thread_checker_;
   bool use_audio_thread_;
+  std::unique_ptr<media::MockAudioManager> audio_manager_;
+  std::unique_ptr<media::AudioSystem> audio_system_;
   base::Thread audio_thread_;
-  MockAudioManager::UniquePtr audio_manager_;
-  std::unique_ptr<media::AudioSystem> audio_system_;
   AudioParameters input_params_;
   AudioParameters output_params_;
   AudioParameters default_output_params_;
   AudioDeviceDescriptions input_device_descriptions_;
   AudioDeviceDescriptions output_device_descriptions_;
 };
 
 TEST_P(AudioSystemImplTest, GetInputStreamParameters) {
   EXPECT_CALL(*this, AudioParametersReceived());
   audio_system_->GetInputStreamParameters(
@@ skipping 118 matching lines @@
   audio_system_->GetDeviceDescriptions(
       base::Bind(&AudioSystemImplTest::OnGetDeviceDescriptions,
                  base::Unretained(this), output_device_descriptions_),
       false);
   WaitForCallback();
 }
 
 INSTANTIATE_TEST_CASE_P(, AudioSystemImplTest, testing::Values(false, true));
 
 }  // namespace media