Add still image capture interface for VideoCaptureDevice.

media/video/capture/video_capture_types.cc

Index: media/video/capture/video_capture_types.cc
diff --git a/media/video/capture/video_capture_types.cc b/media/video/capture/video_capture_types.cc
index 17f2d654c6193e697b8dbc9a188bcaa099d4e74d..f346827eeefd2c0d90dce6fda746011513b19941 100644
--- a/media/video/capture/video_capture_types.cc
+++ b/media/video/capture/video_capture_types.cc
@@ -19,6 +19,14 @@ VideoCaptureFormat::VideoCaptureFormat(const gfx::Size& frame_size,
       frame_rate(frame_rate),
       pixel_format(pixel_format) {}
 
+ImageCaptureFormat::ImageCaptureFormat() : pixel_format(PIXEL_FORMAT_UNKNOWN) {
+}
+
+ImageCaptureFormat::ImageCaptureFormat(const gfx::Size& frame_size,
+                                       VideoPixelFormat pixel_format)
+    : frame_size(frame_size), pixel_format(pixel_format) {
+}
+
 bool VideoCaptureFormat::IsValid() const {
   return (frame_size.width() < media::limits::kMaxDimension) &&
          (frame_size.height() < media::limits::kMaxDimension) &&