Remove TODO saying to remove WebRtcVideoFrame.

Comment was added prematurely, there's no decision to get rid of this
type.

BUG=1788
R=pthatcher@webrtc.org

Review URL: https://webrtc-codereview.appspot.com/19049004

git-svn-id: http://webrtc.googlecode.com/svn/trunk@6894 4adac7df-926f-26a2-2b94-8c16560cd09d

talk/media/webrtc/webrtcvideoengine2.cc

@@ -661,8 +661,6 @@ class WebRtcVideoRenderFrame : public VideoFrame {
                                        size_t pixel_height,
                                        int64 elapsed_time,
                                        int64 time_stamp) const OVERRIDE {
-    // TODO(pbos): Remove WebRtcVideoFrame dependency, and have a non-const
-    // version of I420VideoFrame wrapped.
     WebRtcVideoFrame* frame = new WebRtcVideoFrame();
     frame->InitToBlack(
         w, h, pixel_width, pixel_height, elapsed_time, time_stamp);