GN: Enable ARC for Mac and iOS in rtc_* templates

webrtc/sdk/objc/Framework/UnitTests/avformatmappertests.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 79 matching lines @@
                     minFps:0.0
                     maxFps:60.0];
   return instance;
 }
 
 - (void)dealloc {
   if (_format != nil) {
     CFRelease(_format);
     _format = nil;
   }
-  [super dealloc];
 }
 
 // Redefinition of AVCaptureDevice methods we want to mock.
 - (CMVideoFormatDescriptionRef)formatDescription {
   return self.format;
 }
 
 - (NSArray *)videoSupportedFrameRateRanges {
   return @[ self.rangeMock ];
 }
@@ skipping 127 matching lines @@
   //https://github.com/erikdoe/ocmock/issues/241
   @try {
     [mockDevice verify];
   } @catch (NSException* exception) {
     if ([exception.reason isEqual:testException.reason]) {
       // Nothing dangerous here
       EXPECT_TRUE([exception.reason isEqualToString:exception.reason]);
     }
   }
 }