Revert of Delete deprecated and transitional stuff related to video frame refactoring.

webrtc/sdk/objc/Framework/Classes/objcvideotracksource.mm

 /*
  *  Copyright (c) 2017 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.
  */
 
 #include "webrtc/sdk/objc/Framework/Classes/objcvideotracksource.h"
 
 #import "RTCVideoFrame+Private.h"
 
-#include "webrtc/api/video/i420_buffer.h"
 #include "webrtc/common_video/include/corevideo_frame_buffer.h"
 
 namespace webrtc {
 
 ObjcVideoTrackSource::ObjcVideoTrackSource() {}
 
 void ObjcVideoTrackSource::OnOutputFormatRequest(int width, int height, int fps) {
   cricket::VideoFormat format(width, height, cricket::VideoFormat::FpsToInterval(fps), 0);
   video_adapter()->OnOutputFormatRequest(format);
 }
@@ skipping 28 matching lines @@
     // TODO(magjed): Optimize this I420 path.
     rtc::scoped_refptr<I420Buffer> i420_buffer = I420Buffer::Create(adapted_width, adapted_height);
     i420_buffer->CropAndScaleFrom(*frame.videoBuffer, crop_x, crop_y, crop_width, crop_height);
     buffer = i420_buffer;
   }
 
   // Applying rotation is only supported for legacy reasons and performance is
   // not critical here.
   webrtc::VideoRotation rotation = static_cast<webrtc::VideoRotation>(frame.rotation);
   if (apply_rotation() && rotation != kVideoRotation_0) {
-    buffer = I420Buffer::Rotate(*buffer->NativeToI420Buffer(), rotation);
+    buffer = I420Buffer::Rotate(buffer->NativeToI420Buffer(), rotation);
     rotation = kVideoRotation_0;
   }
 
   OnFrame(webrtc::VideoFrame(buffer, rotation, translated_timestamp_us));
 }
 
 }  // namespace webrtc