Move RTCI420Frame with minor style changes.

webrtc/api/BUILD.gn

 # Copyright (c) 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.
 
 import("../build/webrtc.gni")
 
@@ skipping 11 matching lines @@
       # Add RTCIceCandidate when there's a BUILD.gn for peer connection APIs
       #"objc/RTCIceCandidate+Private.h",
       #"objc/RTCIceCandidate.h",
       #"objc/RTCIceCandidate.mm",
       "objc/RTCIceServer+Private.h",
       "objc/RTCIceServer.h",
       "objc/RTCIceServer.mm",
       "objc/RTCSessionDescription+Private.h",
       "objc/RTCSessionDescription.h",
       "objc/RTCSessionDescription.mm",
+      "objc/RTCVideoFrame+Private.h",
+      "objc/RTCVideoFrame.h",
+      "objc/RTCVideoFrame.mm",
       "objc/WebRTC-Prefix.pch",
     ]
   }
 }