New static I420Buffer::Rotate method, to replace GetCopyWithRotationApplied.

webrtc/media/base/videoframe.h

Index: webrtc/media/base/videoframe.h
diff --git a/webrtc/media/base/videoframe.h b/webrtc/media/base/videoframe.h
index a1393499f9e72742ba5792e790c09cf5fe52baf5..d0d7b48ee6abdaad9c372b9ac581493795948da6 100644
--- a/webrtc/media/base/videoframe.h
+++ b/webrtc/media/base/videoframe.h
@@ -71,9 +71,9 @@ class VideoFrame {
   // Return a copy of frame which has its pending rotation applied. The
   // ownership of the returned frame is held by this frame.
 
-  // TODO(nisse): Deprecated. Should be moved or deleted in the
-  // cricket::VideoFrame and webrtc::VideoFrame merge, possibly with a helper
-  // method on VideoFrameBuffer.
+  // TODO(nisse): Deprecated, no longer used within webrtc. Should be
+  // deleted as soon as downstream applications are updated. Use
+  // webrtc::I420Buffer::Rotate instead.
   virtual const VideoFrame* GetCopyWithRotationApplied() const = 0;
 
   // Converts the I420 data to RGB of a certain type such as ARGB and ABGR.