Revert of Rename AppRTCDemo on Android and iOS to AppRTCMobile (patchset #2 id:20001 of https://codereview.webrtc.org/2343403002/ )

Reason for revert:
Breaks internal project.

Original issue's description:
> Rename AppRTCDemo on Android and iOS to AppRTCMobile
>
> The purpose is to make it clearer it is a mobile application.
>
> BUG=webrtc:6359
> NOPRESUBMIT=true
>
> Committed: https://crrev.com/d3af58bdab5b25acd62cd816363becc7003d3e5a
> Cr-Commit-Position: refs/heads/master@{#14356}

TBR=sakal@webrtc.org,kthelgason@webrtc.org,tommi@webrtc.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=webrtc:6359

Review-Url: https://codereview.webrtc.org/2358133003
Cr-Commit-Position: refs/heads/master@{#14358}

webrtc/examples/objc/AppRTCMobile/ios/ARDVideoCallViewController.h

@@ -1,31 +0,0 @@
-/*
- *  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.
- */
-
-#import <UIKit/UIKit.h>
-
-@class ARDVideoCallViewController;
-@protocol ARDVideoCallViewControllerDelegate <NSObject>
-
-- (void)viewControllerDidFinish:(ARDVideoCallViewController *)viewController;
-
-@end
-
-@interface ARDVideoCallViewController : UIViewController
-
-@property(nonatomic, weak) id<ARDVideoCallViewControllerDelegate> delegate;
-
-- (instancetype)initForRoom:(NSString *)room
-                 isLoopback:(BOOL)isLoopback
-                isAudioOnly:(BOOL)isAudioOnly
-          shouldMakeAecDump:(BOOL)shouldMakeAecDump
-      shouldUseLevelControl:(BOOL)shouldUseLevelControl
-                   delegate:(id<ARDVideoCallViewControllerDelegate>)delegate;
-
-@end