Pass camera facing info to audio client

content/browser/renderer_host/media/video_capture_manager.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.
 
 // VideoCaptureManager is used to open/close, start/stop, enumerate available
 // video capture devices, and manage VideoCaptureController's.
 // All functions are expected to be called from Browser::IO thread. Some helper
 // functions (*OnDeviceThread) will dispatch operations to the device thread.
 // VideoCaptureManager will open OS dependent instances of VideoCaptureDevice.
 // A device can only be opened once.
 
 #ifndef CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_MANAGER_H_
 #define CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_MANAGER_H_
 
 #include <list>
 #include <map>
 #include <set>
 #include <string>
 
 #include "base/macros.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "base/message_loop/message_loop.h"
+#include "base/observer_list.h"
 #include "base/process/process_handle.h"
 #include "base/threading/thread_checker.h"
 #include "base/timer/elapsed_timer.h"
 #include "build/build_config.h"
 #include "content/browser/renderer_host/media/media_stream_provider.h"
 #include "content/browser/renderer_host/media/video_capture_controller_event_handler.h"
 #include "content/common/content_export.h"
 #include "content/common/media/media_stream_options.h"
+#include "media/base/video_facing.h"
 #include "media/capture/video/video_capture_device.h"
 #include "media/capture/video/video_capture_device_factory.h"
 #include "media/capture/video_capture_types.h"
 
 #if defined(OS_ANDROID)
 #include "base/android/application_status_listener.h"
 #endif
 
 namespace content {
 class VideoCaptureController;
 class VideoCaptureControllerEventHandler;
 
 // VideoCaptureManager opens/closes and start/stops video capture devices.
 class CONTENT_EXPORT VideoCaptureManager : public MediaStreamProvider {
  public:
   using VideoCaptureDevice = media::VideoCaptureDevice;
 
   // Callback used to signal the completion of a controller lookup.
   using DoneCB =
       base::Callback<void(const base::WeakPtr<VideoCaptureController>&)>;
 
   explicit VideoCaptureManager(
       std::unique_ptr<media::VideoCaptureDeviceFactory> factory);
 
+  // AddVideoCaptureObserver() can be called only before any devices are opened.
+  // RemoveAllVideoCaptureObservers() can be called only after all devices
+  // are closed.
+  // They can be called more than once and it's ok to not call at all if the
+  // client is not interested in receiving media::VideoCaptureObserver callacks.
+  // This methods can be called on whatever thread. The callbacks of
+  // media::VideoCaptureObserver arrive on browser IO thread.
+  void AddVideoCaptureObserver(media::VideoCaptureObserver* observer);
+  void RemoveAllVideoCaptureObservers();
+
   void Unregister();
 
   // Implements MediaStreamProvider.
   void Register(MediaStreamProviderListener* listener,
                 const scoped_refptr<base::SingleThreadTaskRunner>&
                     device_task_runner) override;
   int Open(const StreamDeviceInfo& device) override;
   void Close(int capture_session_id) override;
 
   // Called by VideoCaptureHost to locate a capture device for |capture_params|,
@@ skipping 263 matching lines @@
   // Queue to keep photo-associated requests waiting for a device to initialize,
   // bundles a session id integer and an associated photo-related request.
   std::list<std::pair<int, base::Callback<void(media::VideoCaptureDevice*)>>>
       photo_request_queue_;
 
   // Device creation factory injected on construction from MediaStreamManager or
   // from the test harness.
   std::unique_ptr<media::VideoCaptureDeviceFactory>
       video_capture_device_factory_;
 
+  base::ObserverList<media::VideoCaptureObserver> capture_observers_;

[chfremer, 2017/02/13 19:00:15]

Nice! I didn't even know we had something like that in base.

+
   // Local cache of the enumerated video capture devices' names and capture
   // supported formats. A snapshot of the current devices and their capabilities
   // is composed in VideoCaptureDeviceFactory::EnumerateDeviceNames() and
   // ConsolidateDevicesInfoOnDeviceThread(), and this snapshot is used to update
   // this list in OnDevicesInfoEnumerated(). GetDeviceSupportedFormats() will
   // use this list if the device is not started, otherwise it will retrieve the
   // active device capture format from the VideoCaptureController associated.
   DeviceInfos devices_info_cache_;
 
   // Map used by DesktopCapture.
   std::map<media::VideoCaptureSessionId, gfx::NativeViewId>
       notification_window_ids_;
 
   DISALLOW_COPY_AND_ASSIGN(VideoCaptureManager);
 };
 
 }  // namespace content
 
 #endif  // CONTENT_BROWSER_RENDERER_HOST_MEDIA_VIDEO_CAPTURE_MANAGER_H_