Add VideoCaptureDevice::GetDeviceSupportedFormats to interface + implementation for Linux and Fake

media/video/capture/video_capture_device_dummy.h

Index: media/video/capture/video_capture_device_dummy.h
diff --git a/media/video/capture/video_capture_device_dummy.h b/media/video/capture/video_capture_device_dummy.h
index c4a95cb0ce28f98c71a9d7ac57e8422cded804cf..5fa09690c5c6e7baec7b23f5a18fb802e2b1fb52 100644
--- a/media/video/capture/video_capture_device_dummy.h
+++ b/media/video/capture/video_capture_device_dummy.h
@@ -24,6 +24,9 @@ class VideoCaptureDeviceDummy : public VideoCaptureDevice {
   virtual void Start() OVERRIDE;
   virtual void Stop() OVERRIDE;
   virtual void DeAllocate() OVERRIDE;
+  virtual void GetDeviceSupportedFormats(
+      const std::string& device_name,
+      VideoCaptureFormats* capture_formats) OVERRIDE;
 
  private:
   VideoCaptureDeviceDummy();