Update iOS AppRTCDemo to use level controller.

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

Index: webrtc/examples/objc/AppRTCDemo/ios/ARDMainViewController.m
diff --git a/webrtc/examples/objc/AppRTCDemo/ios/ARDMainViewController.m b/webrtc/examples/objc/AppRTCDemo/ios/ARDMainViewController.m
index 21f00cb4c0447070a64f3d22de3386f6afa94db8..e392168dee61b3e2dee72a224c593cad3fc3862e 100644
--- a/webrtc/examples/objc/AppRTCDemo/ios/ARDMainViewController.m
+++ b/webrtc/examples/objc/AppRTCDemo/ios/ARDMainViewController.m
@@ -54,11 +54,12 @@
 #pragma mark - ARDMainViewDelegate
 
 - (void)mainView:(ARDMainView *)mainView
-         didInputRoom:(NSString *)room
-           isLoopback:(BOOL)isLoopback
-          isAudioOnly:(BOOL)isAudioOnly
-    shouldMakeAecDump:(BOOL)shouldMakeAecDump
-    useManualAudio:(BOOL)useManualAudio {
+             didInputRoom:(NSString *)room
+               isLoopback:(BOOL)isLoopback
+              isAudioOnly:(BOOL)isAudioOnly
+        shouldMakeAecDump:(BOOL)shouldMakeAecDump
+    shouldUseLevelControl:(BOOL)shouldUseLevelControl
+           useManualAudio:(BOOL)useManualAudio {
   if (!room.length) {
     [self showAlertWithMessage:@"Missing room name."];
     return;
@@ -98,6 +99,7 @@
                                            isLoopback:isLoopback
                                           isAudioOnly:isAudioOnly
                                     shouldMakeAecDump:shouldMakeAecDump
+                                shouldUseLevelControl:shouldUseLevelControl
                                              delegate:self];
   videoCallViewController.modalTransitionStyle =
       UIModalTransitionStyleCrossDissolve;