Ensures that audio tasks cannot run after AudioManager is deleted.

media/audio/mac/audio_auhal_mac_unittest.cc

 // Copyright 2013 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 "base/bind.h"
 #include "base/macros.h"
 #include "base/run_loop.h"
 #include "base/synchronization/waitable_event.h"
 #include "base/test/test_message_loop.h"
 #include "base/threading/thread_task_runner_handle.h"
@@ skipping 41 matching lines @@
   }
 
   bool OutputDevicesAvailable() {
     return manager_->HasAudioOutputDevices();
   }
 
   void OnLogMessage(const std::string& message) { log_message_ = message; }
 
  protected:
   base::TestMessageLoop message_loop_;
-  ScopedAudioManagerPtr manager_;
+  std::unique_ptr<AudioManager> manager_;
   MockAudioSourceCallback source_;
   std::string log_message_;
 
  private:
   DISALLOW_COPY_AND_ASSIGN(AUHALStreamTest);
 };
 
 TEST_F(AUHALStreamTest, HardwareSampleRate) {
   ABORT_AUDIO_TEST_IF_NOT(OutputDevicesAvailable());
   const AudioParameters preferred_params =
@@ skipping 35 matching lines @@
   stream->Start(&source_);
   event.Wait();
 
   stream->Stop();
   stream->Close();
 
   EXPECT_FALSE(log_message_.empty());
 }
 
 }  // namespace media