Revert of Delete webrtc::VideoFrame methods buffer and stride.

webrtc/video_frame.h

Index: webrtc/video_frame.h
diff --git a/webrtc/video_frame.h b/webrtc/video_frame.h
index 4dc3411e98ac2d218077d552d6ceb4cc52f28444..409abf3446f1961eedfcde579a8fee2083691088 100644
--- a/webrtc/video_frame.h
+++ b/webrtc/video_frame.h
@@ -65,8 +65,16 @@
   // reference to the video buffer also retained by |videoFrame|.
   void ShallowCopy(const VideoFrame& videoFrame);
 
+  // Get pointer to buffer per plane.
+  uint8_t* buffer(PlaneType type);
+  // Overloading with const.
+  const uint8_t* buffer(PlaneType type) const;
+
   // Get allocated size per plane.
   int allocated_size(PlaneType type) const;
+
+  // Get allocated stride per plane.
+  int stride(PlaneType type) const;
 
   // Get frame width.
   int width() const;
@@ -116,10 +124,7 @@
 
   // Return the underlying buffer. Never nullptr for a properly
   // initialized VideoFrame.
-  // Creating a new reference breaks the HasOneRef and IsMutable
-  // logic. So return a const ref to our reference.
-  const rtc::scoped_refptr<webrtc::VideoFrameBuffer>& video_frame_buffer()
-      const;
+  rtc::scoped_refptr<webrtc::VideoFrameBuffer> video_frame_buffer() const;
 
   // Set the underlying buffer.
   void set_video_frame_buffer(