Ensures that audio tasks cannot run after AudioManager is deleted.

media/audio/cras/cras_unified_unittest.cc

Index: media/audio/cras/cras_unified_unittest.cc
diff --git a/media/audio/cras/cras_unified_unittest.cc b/media/audio/cras/cras_unified_unittest.cc
index 89f943806c8c8f5af1ba07d401e30213d9124d6d..3bb52fc7244cf5acd738bd11a980ab3b5dc98f25 100644
--- a/media/audio/cras/cras_unified_unittest.cc
+++ b/media/audio/cras/cras_unified_unittest.cc
@@ -18,6 +18,7 @@
 #include "media/audio/cras/audio_manager_cras.h"
 #include "media/audio/fake_audio_log_factory.h"
 #include "media/audio/mock_audio_source_callback.h"
+#include "media/audio/test_audio_thread.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
@@ -39,8 +40,7 @@ namespace media {
 class MockAudioManagerCras : public AudioManagerCras {
  public:
   MockAudioManagerCras()
-      : AudioManagerCras(base::ThreadTaskRunnerHandle::Get(),
-                         base::ThreadTaskRunnerHandle::Get(),
+      : AudioManagerCras(base::MakeUnique<TestAudioThread>(),
                          &fake_audio_log_factory_) {}
 
   // We need to override this function in order to skip the checking the number
@@ -63,7 +63,7 @@ class CrasUnifiedStreamTest : public testing::Test {
     base::RunLoop().RunUntilIdle();
   }
 
-  ~CrasUnifiedStreamTest() override {}
+  ~CrasUnifiedStreamTest() override { mock_manager_->Shutdown(); }
 
   CrasUnifiedStream* CreateStream(ChannelLayout layout) {
     return CreateStream(layout, kTestFramesPerPacket);
@@ -88,8 +88,7 @@ class CrasUnifiedStreamTest : public testing::Test {
   static const uint32_t kTestFramesPerPacket;
 
   base::TestMessageLoop message_loop_;
-  std::unique_ptr<StrictMock<MockAudioManagerCras>, AudioManagerDeleter>
-      mock_manager_;
+  std::unique_ptr<StrictMock<MockAudioManagerCras>> mock_manager_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(CrasUnifiedStreamTest);