Switching AudioInputDeviceManager from using AudioManager interface to AudioSystem one.

media/audio/audio_system.h

 // 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.
 
 #ifndef MEDIA_AUDIO_AUDIO_SYSTEM_H_
 #define MEDIA_AUDIO_AUDIO_SYSTEM_H_
 
 #include "base/callback.h"
 #include "media/audio/audio_device_description.h"
 #include "media/base/audio_parameters.h"
 #include "media/base/media_export.h"
 
 namespace base {
 class SingleThreadTaskRunner;
 }
 
 namespace media {
 class AudioManager;
 
 // Work in progress: Provides asynchronous interface to AudioManager. All the
 // AudioManager clients will be switched to it, in preparation for moving
 // to Mojo audio service.
 class MEDIA_EXPORT AudioSystem {
  public:
   // Replies are asynchronously sent from audio system thread to the thread the
-  // call is issued on. Attention! Since audio system thread may outlive all the
-  // others, callbacks must always be bound to weak pointers!
+  // call is issued on. Attention! Audio system thread may outlive the client
+  // objects; bind callbacks with care.
   using OnAudioParamsCallback = base::Callback<void(const AudioParameters&)>;
   using OnBoolCallback = base::Callback<void(bool)>;
   using OnDeviceDescriptionsCallback =
       base::Callback<void(AudioDeviceDescriptions)>;
+  using OnDeviceIdCallback = base::Callback<void(const std::string&)>;
+  using OnInputDeviceInfoCallback = base::Callback<
+      void(const AudioParameters&, const AudioParameters&, const std::string&)>;
 
+  // Must not be called on audio system thread if it differs from the one
+  // AudioSystem is destroyed on. See http://crbug.com/705455.
   static AudioSystem* Get();
 
   virtual ~AudioSystem();
 
   // Callback may receive invalid parameters, it means the specified device is
   // not found. This is best-effort: valid parameters do not guarantee existance
   // of the device.
   // TODO(olka,tommi): fix all AudioManager implementations to return invalid
   // parameters if the device is not found.
   virtual void GetInputStreamParameters(
@@ skipping 11 matching lines @@
       const std::string& device_id,
       OnAudioParamsCallback on_params_cb) const = 0;
 
   virtual void HasInputDevices(OnBoolCallback on_has_devices_cb) const = 0;
 
   virtual void HasOutputDevices(OnBoolCallback on_has_devices_cb) const = 0;
 
   // Replies with device descriptions of input audio devices if |for_input| is
   // true, and of output audio devices otherwise.
   virtual void GetDeviceDescriptions(
-      OnDeviceDescriptionsCallback on_descriptions_cp,
+      OnDeviceDescriptionsCallback on_descriptions_cb,
       bool for_input) = 0;
 
+  // Replies with an empty string if there is no associated output device found.
+  virtual void GetAssociatedOutputDeviceID(
+      const std::string& input_device_id,
+      OnDeviceIdCallback on_device_id_cb) = 0;
+
+  // Replies with audio parameters for the specified input device and audio
+  // parameters and device ID of the associated output device, if any (otherwise
+  // it's AudioParameters() and an empty string).
+  virtual void GetInputDeviceInfo(
+      const std::string& input_device_id,
+      OnInputDeviceInfoCallback on_input_device_info_cb) = 0;
+
   virtual base::SingleThreadTaskRunner* GetTaskRunner() const = 0;
 
-  // Must not be used for anything but stream creation.
-  virtual AudioManager* GetAudioManager() const = 0;
-
  protected:
   // Sets the global AudioSystem pointer to the specified non-null value.
   static void SetInstance(AudioSystem* audio_system);
 
   // Sets the global AudioSystem pointer to null if it equals the specified one.
   static void ClearInstance(const AudioSystem* audio_system);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_AUDIO_AUDIO_SYSTEM_H_