ObjC: Remove RTCVideoFrame.nativeHandle

webrtc/sdk/objc/Framework/Classes/PeerConnection/RTCVideoFrame.mm

 /*
  *  Copyright 2015 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 65 matching lines @@
     return ((id<RTCI420Buffer>)_buffer).strideV;
   } else {
     return 0;
   }
 }
 
 - (int64_t)timeStampNs {
   return _timeStampNs;
 }
 
-- (CVPixelBufferRef)nativeHandle {
-  if ([_buffer isKindOfClass:[RTCCVPixelBuffer class]]) {
-    return ((RTCCVPixelBuffer *)_buffer).pixelBuffer;
-  } else {
-    return nullptr;
-  }
-}
-
 - (RTCVideoFrame *)newI420VideoFrame {
   return [[RTCVideoFrame alloc] initWithBuffer:[_buffer toI420]
                                       rotation:_rotation
                                    timeStampNs:_timeStampNs];
 }
 
 - (instancetype)initWithPixelBuffer:(CVPixelBufferRef)pixelBuffer
                            rotation:(RTCVideoRotation)rotation
                         timeStampNs:(int64_t)timeStampNs {
   return [self initWithBuffer:[[RTCCVPixelBuffer alloc] initWithPixelBuffer:pixelBuffer]
@@ skipping 26 matching lines @@
   if (self = [super init]) {
     _buffer = buffer;
     _rotation = rotation;
     _timeStampNs = timeStampNs;
   }
 
   return self;
 }
 
 @end