Update iOS AppRTCDemo to use level controller.

webrtc/examples/objc/AppRTCDemo/ios/ARDVideoCallViewController.m

 /*
  *  Copyright 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.
  */
 
@@ skipping 22 matching lines @@
   AVAudioSessionPortOverride _portOverride;
 }
 
 @synthesize videoCallView = _videoCallView;
 @synthesize delegate = _delegate;
 
 - (instancetype)initForRoom:(NSString *)room
                  isLoopback:(BOOL)isLoopback
                 isAudioOnly:(BOOL)isAudioOnly
           shouldMakeAecDump:(BOOL)shouldMakeAecDump
+      shouldUseLevelControl:(BOOL)shouldUseLevelControl
                    delegate:(id<ARDVideoCallViewControllerDelegate>)delegate {
   if (self = [super init]) {
     _delegate = delegate;
     _client = [[ARDAppClient alloc] initWithDelegate:self];
     [_client connectToRoomWithId:room
                       isLoopback:isLoopback
                      isAudioOnly:isAudioOnly
-               shouldMakeAecDump:shouldMakeAecDump];
+               shouldMakeAecDump:shouldMakeAecDump
+           shouldUseLevelControl:shouldUseLevelControl];
   }
   return self;
 }
 
 - (void)loadView {
   _videoCallView = [[ARDVideoCallView alloc] initWithFrame:CGRectZero];
   _videoCallView.delegate = self;
   _videoCallView.statusLabel.text =
       [self statusTextForState:RTCIceConnectionStateNew];
   self.view = _videoCallView;
@@ skipping 150 matching lines @@
 - (void)showAlertWithMessage:(NSString*)message {
   UIAlertView* alertView = [[UIAlertView alloc] initWithTitle:nil
                                                       message:message
                                                      delegate:nil
                                             cancelButtonTitle:@"OK"
                                             otherButtonTitles:nil];
   [alertView show];
 }
 
 @end