Revert of Delete method cricket::VideoFrame::Copy.

webrtc/media/base/videoframe.h

 /*
  *  Copyright (c) 2004 The WebRTC project authors. All Rights Reserved.
  *
  *  Use of this source code is governed by a BSD-style license
  *  that can be found in the LICENSE file in the root of the source
  *  tree. An additional intellectual property rights grant can be found
  *  in the file PATENTS.  All contributing project authors may
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
@@ skipping 33 matching lines @@
   virtual int64_t GetTimeStamp() const {
     return rtc::kNumNanosecsPerMicrosec * timestamp_us();
   }
   virtual void SetTimeStamp(int64_t time_ns) {
     set_timestamp_us(time_ns / rtc::kNumNanosecsPerMicrosec);
   }
 
   // Indicates the rotation angle in degrees.
   virtual webrtc::VideoRotation rotation() const = 0;
 
+  // Make a shallow copy of the frame. The frame buffer itself is not copied.
+  // Both the current and new VideoFrame will share a single reference-counted
+  // frame buffer.
+  virtual VideoFrame *Copy() const = 0;
+
   // Return a copy of frame which has its pending rotation applied. The
   // ownership of the returned frame is held by this frame.
   virtual const VideoFrame* GetCopyWithRotationApplied() const = 0;
 
   // Converts the I420 data to RGB of a certain type such as ARGB and ABGR.
   // Returns the frame's actual size, regardless of whether it was written or
   // not (like snprintf). Parameters size and stride_rgb are in units of bytes.
   // If there is insufficient space, nothing is written.
   virtual size_t ConvertToRgbBuffer(uint32_t to_fourcc,
                                     uint8_t* buffer,
@@ skipping 12 matching lines @@
   virtual VideoFrame* CreateEmptyFrame(int w,
                                        int h,
                                        int64_t timestamp_us) const = 0;
 
   virtual void set_rotation(webrtc::VideoRotation rotation) = 0;
 };
 
 }  // namespace cricket
 
 #endif  // WEBRTC_MEDIA_BASE_VIDEOFRAME_H_