Update I420Buffer to new VideoFrameBuffer interface

webrtc/test/testsupport/metrics/video_metrics.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 20 matching lines @@
 // Used for calculating min and max values.
 static bool LessForFrameResultValue(const FrameResult& s1,
                                     const FrameResult& s2) {
   return s1.value < s2.value;
 }
 
 enum VideoMetricsType { kPSNR, kSSIM, kBoth };
 
 // Calculates metrics for a frame and adds statistics to the result for it.
 void CalculateFrame(VideoMetricsType video_metrics_type,
-                    const VideoFrameBuffer& ref,
-                    const VideoFrameBuffer& test,
+                    const I420BufferInterface& ref,
+                    const I420BufferInterface& test,
                     int frame_number,
                     QualityMetricsResult* result) {
   FrameResult frame_result = {0, 0};
   frame_result.frame_number = frame_number;
   switch (video_metrics_type) {
     case kPSNR:
       frame_result.value = I420PSNR(ref, test);
       break;
     case kSSIM:
       frame_result.value = I420SSIM(ref, test);
@@ skipping 131 matching lines @@
                       int width,
                       int height,
                       QualityMetricsResult* result) {
   assert(result != NULL);
   return CalculateMetrics(kSSIM, ref_filename, test_filename, width, height,
                           NULL, result);
 }
 
 }  // namespace test
 }  // namespace webrtc