ImageCapture: Implement takePhoto() for Windows

media/capture/video/win/video_capture_device_win.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.
 
 // Windows specific implementation of VideoCaptureDevice. DirectShow is used for
 // capturing. DirectShow provide its own threads for capturing.
 
 #ifndef MEDIA_CAPTURE_VIDEO_WIN_VIDEO_CAPTURE_DEVICE_WIN_H_
 #define MEDIA_CAPTURE_VIDEO_WIN_VIDEO_CAPTURE_DEVICE_WIN_H_
 
@@ skipping 57 matching lines @@
       const VideoCaptureDeviceDescriptor& device_descriptor);
   ~VideoCaptureDeviceWin() override;
   // Opens the device driver for this device.
   bool Init();
 
   // VideoCaptureDevice implementation.
   void AllocateAndStart(
       const VideoCaptureParams& params,
       std::unique_ptr<VideoCaptureDevice::Client> client) override;
   void StopAndDeAllocate() override;
+  void TakePhoto(TakePhotoCallback callback) override;
 
  private:
   enum InternalState {
     kIdle,       // The device driver is opened but camera is not in use.
     kCapturing,  // Video is being captured.
     kError       // Error accessing HW functions.
                  // User needs to recover by destroying the object.
   };
 
   // Implements SinkFilterObserver.
@@ skipping 20 matching lines @@
   base::win::ScopedComPtr<IPin> output_capture_pin_;
 
   scoped_refptr<SinkFilter> sink_filter_;
 
   // Map of all capabilities this device support.
   CapabilityList capabilities_;
   VideoCaptureFormat capture_format_;
 
   base::TimeTicks first_ref_time_;
 
+  std::queue<TakePhotoCallback> take_photo_callbacks_;
+
   base::ThreadChecker thread_checker_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(VideoCaptureDeviceWin);
 };
 
 }  // namespace media
 
 #endif  // MEDIA_CAPTURE_VIDEO_WIN_VIDEO_CAPTURE_DEVICE_WIN_H_