Update iOS AppRTCDemo to use level controller.

NOTRY=True
BUG=

Review-Url: https://codereview.webrtc.org/2294913003
Cr-Commit-Position: refs/heads/master@{#13977}
diff --git a/webrtc/examples/objc/AppRTCDemo/ios/ARDMainView.h b/webrtc/examples/objc/AppRTCDemo/ios/ARDMainView.h
index e9f4991..81f9d00 100644
--- a/webrtc/examples/objc/AppRTCDemo/ios/ARDMainView.h
+++ b/webrtc/examples/objc/AppRTCDemo/ios/ARDMainView.h
@@ -15,11 +15,12 @@
 @protocol ARDMainViewDelegate <NSObject>
 
 - (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;
 
 - (void)mainViewDidToggleAudioLoop:(ARDMainView *)mainView;