Split iOS sdk in to separate targets

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

 /*
  *  Copyright 2016 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 12 matching lines @@
 
   NSMutableArray *metrics =
       [NSMutableArray arrayWithCapacity:histograms.size()];
   for (auto const &histogram : histograms) {
     RTCMetricsSampleInfo *metric = [[RTCMetricsSampleInfo alloc]
         initWithNativeSampleInfo:*histogram.second];
     [metrics addObject:metric];
   }
   return metrics;
 }