Convert some audio code to OnceCallback.

content/browser/renderer_host/media/audio_renderer_host.h

 // Copyright (c) 2012 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.
 //
 // AudioRendererHost serves audio related requests from AudioRenderer which
 // lives inside the render process and provide access to audio hardware.
 //
 // This class is owned by RenderProcessHostImpl, and instantiated on UI
 // thread, but all other operations and method calls happen on IO thread, so we
 // need to be extra careful about the lifetime of this object. AudioManager is a
@@ skipping 85 matching lines @@
 
  private:
   friend class AudioRendererHostTest;
   friend class BrowserThread;
   friend class base::DeleteHelper<AudioRendererHost>;
   friend class MockAudioRendererHost;
   friend class TestAudioRendererHost;
   FRIEND_TEST_ALL_PREFIXES(AudioRendererHostTest, CreateMockStream);
   FRIEND_TEST_ALL_PREFIXES(AudioRendererHostTest, MockStreamDataConversation);
 
-  // Internal callback type for access requests to output devices.
-  // |have_access| is true only if there is permission to access the device.
-  typedef base::Callback<void(bool have_access)> OutputDeviceAccessCB;
-
   using AudioOutputDelegateVector =
       std::vector<std::unique_ptr<media::AudioOutputDelegate>>;
 
   // The type of a function that is run on the UI thread to check whether the
   // routing IDs reference a valid RenderFrameHost. The function then runs
   // |callback| on the IO thread with true/false if valid/invalid.
   using ValidateRenderFrameIdFunction =
       void (*)(int render_process_id,
                int render_frame_id,
-               const base::Callback<void(bool)>& callback);
+               base::OnceCallback<void(bool)> callback);
 
   ~AudioRendererHost() override;
 
   // Methods called on IO thread ----------------------------------------------
 
   // Audio related IPC message handlers.
 
   // Request permission to use an output device for use by a stream produced
   // in the RenderFrame referenced by |render_frame_id|.
   // |session_id| is used for unified IO to find out which input device to be
@@ skipping 92 matching lines @@
   ValidateRenderFrameIdFunction validate_render_frame_id_function_;
 
   AudioOutputAuthorizationHandler authorization_handler_;
 
   DISALLOW_COPY_AND_ASSIGN(AudioRendererHost);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_AUDIO_RENDERER_HOST_H_