Add ability to retrieve capabilities for audio input devices to MediaDevicesDispatcherHost.

content/browser/renderer_host/media/media_devices_dispatcher_host.h

Index: content/browser/renderer_host/media/media_devices_dispatcher_host.h
diff --git a/content/browser/renderer_host/media/media_devices_dispatcher_host.h b/content/browser/renderer_host/media/media_devices_dispatcher_host.h
index f37e9906ad4be45e84a954e035cc15672510b9b6..47fc6a7500927b5abf02874a2f0e36f65652d109 100644
--- a/content/browser/renderer_host/media/media_devices_dispatcher_host.h
+++ b/content/browser/renderer_host/media/media_devices_dispatcher_host.h
@@ -51,6 +51,8 @@ class CONTENT_EXPORT MediaDevicesDispatcherHost
                         EnumerateDevicesCallback client_callback) override;
   void GetVideoInputCapabilities(
       GetVideoInputCapabilitiesCallback client_callback) override;
+  void GetAudioInputCapabilities(
+      GetAudioInputCapabilitiesCallback client_callback) override;
   void SubscribeDeviceChangeNotifications(MediaDeviceType type,
                                           uint32_t subscription_id) override;
   void UnsubscribeDeviceChangeNotifications(MediaDeviceType type,
@@ -102,6 +104,20 @@ class CONTENT_EXPORT MediaDevicesDispatcherHost
       const std::string& default_device_id,
       const media::VideoCaptureDeviceDescriptors& device_descriptors);
 
+  void GetDefaultAudioInputDeviceID(
+      GetAudioInputCapabilitiesCallback client_callback,
+      const url::Origin& security_origin);
+
+  void GotDefaultAudioInputDeviceID(const std::string& default_device_id);
+
+  void GotAudioInputEnumeration(const std::string& default_device_id,
+                                const MediaDeviceEnumeration& enumeration);
+
+  void GotAudioInputParameters(size_t index,
+                               const media::AudioParameters& parameters);
+
+  void FinalizeGetAudioInputCapabilities();
+
   // Returns the currently supported video formats for the given |device_id|.
   media::VideoCaptureFormats GetVideoInputFormats(const std::string& device_id);
 
@@ -124,6 +140,14 @@ class CONTENT_EXPORT MediaDevicesDispatcherHost
   ::mojom::MediaDevicesListenerPtr device_change_listener_;
   url::Origin security_origin_for_testing_;
 
+  struct AudioInputCapabilitiesRequest;
+  // Queued requests for audio-input capabilities.
+  std::vector<AudioInputCapabilitiesRequest>
+      pending_audio_input_capabilities_requests_;
+  size_t num_pending_audio_input_parameters_;
+  std::vector<::mojom::AudioInputDeviceCapabilities>
+      current_audio_input_capabilities_;
+
   base::WeakPtrFactory<MediaDevicesDispatcherHost> weak_factory_;
 
   DISALLOW_COPY_AND_ASSIGN(MediaDevicesDispatcherHost);