Ensures that audio tasks cannot run after AudioManager is deleted.

media/audio/cras/cras_input_unittest.cc

Index: media/audio/cras/cras_input_unittest.cc
diff --git a/media/audio/cras/cras_input_unittest.cc b/media/audio/cras/cras_input_unittest.cc
index 5b848945ca85abc674f47f94bcc7b714bbef346d..a041847679a4b3289eb24a6115bdc4c4dab21bd8 100644
--- a/media/audio/cras/cras_input_unittest.cc
+++ b/media/audio/cras/cras_input_unittest.cc
@@ -68,7 +68,11 @@ class CrasInputStreamTest : public testing::Test {
     base::RunLoop().RunUntilIdle();
   }
 
-  ~CrasInputStreamTest() override {}
+  ~CrasInputStreamTest() override {
+    mock_manager_->GetTaskRunner()->PostTask(
+        FROM_HERE, base::Bind(&media::AudioManager::Shutdown,
+                              base::Unretained(mock_manager_.get())));
+  }
 
   CrasInputStream* CreateStream(ChannelLayout layout) {
     return CreateStream(layout, kTestFramesPerPacket);
@@ -125,8 +129,7 @@ class CrasInputStreamTest : public testing::Test {
   static const int kTestSampleRate;
 
   base::TestMessageLoop message_loop_;
-  std::unique_ptr<StrictMock<MockAudioManagerCrasInput>, AudioManagerDeleter>
-      mock_manager_;
+  std::unique_ptr<StrictMock<MockAudioManagerCrasInput>> mock_manager_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(CrasInputStreamTest);