Delete ShallowCopy, in favor of copy construction and assignment.

webrtc/common_video/video_frame.cc

Index: webrtc/common_video/video_frame.cc
diff --git a/webrtc/common_video/video_frame.cc b/webrtc/common_video/video_frame.cc
index 3e408d5627de2e5d4144b0ad5529ba779a80b3fa..eb59bd35c121ec6c5fe4aed05060453da45008ca 100644
--- a/webrtc/common_video/video_frame.cc
+++ b/webrtc/common_video/video_frame.cc
@@ -51,14 +51,6 @@ VideoFrame::VideoFrame(const rtc::scoped_refptr<VideoFrameBuffer>& buffer,
   RTC_DCHECK(buffer);
 }
 
-void VideoFrame::ShallowCopy(const VideoFrame& videoFrame) {
-  video_frame_buffer_ = videoFrame.video_frame_buffer();
-  timestamp_rtp_ = videoFrame.timestamp_rtp_;
-  ntp_time_ms_ = videoFrame.ntp_time_ms_;
-  timestamp_us_ = videoFrame.timestamp_us_;
-  rotation_ = videoFrame.rotation_;
-}
-
 int VideoFrame::width() const {
   return video_frame_buffer_ ? video_frame_buffer_->width() : 0;
 }