Delete I420 encoder and decoder.

webrtc/modules/video_coding/codecs/test/videoprocessor.cc

 /*
  *  Copyright (c) 2012 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 385 matching lines @@
     default:
       assert(false);
       return "Unknown";
   }
 }
 
 const char* VideoCodecTypeToStr(webrtc::VideoCodecType e) {
   switch (e) {
     case kVideoCodecVP8:
       return "VP8";
-    case kVideoCodecI420:
-      return "I420";
     case kVideoCodecRED:
       return "RED";
     case kVideoCodecULPFEC:
       return "ULPFEC";
     case kVideoCodecUnknown:
       return "Unknown";
     default:
       assert(false);
       return "Unknown";
   }
@@ skipping 13 matching lines @@
 }
 int32_t VideoProcessorImpl::VideoProcessorDecodeCompleteCallback::Decoded(
     VideoFrame& image) {
   // Forward to parent class.
   video_processor_->FrameDecoded(image);
   return 0;
 }
 
 }  // namespace test
 }  // namespace webrtc