Convert ios_web_view_shell to pure Objective-C.

ios/web_view/shell/shell_app_delegate.m

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #import "ios/web_view/shell/shell_app_delegate.h"
 
 #import "ios/web_view/public/criwv.h"
 #import "ios/web_view/shell/shell_delegate.h"
 #import "ios/web_view/shell/shell_view_controller.h"
 
 #if !defined(__has_feature) || !__has_feature(objc_arc)
 #error "This file requires ARC support."
 #endif
 
 @interface ShellAppDelegate ()
-@property (nonatomic, strong) ShellDelegate* delegate;
+@property(nonatomic, strong) ShellDelegate* delegate;
 @end
 
 @implementation ShellAppDelegate
 
 @synthesize delegate = _delegate;
 @synthesize window = _window;
 
 - (BOOL)application:(UIApplication*)application
     didFinishLaunchingWithOptions:(NSDictionary*)launchOptions {
   self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
@@ skipping 20 matching lines @@
 }
 
 - (void)applicationDidBecomeActive:(UIApplication*)application {
 }
 
 - (void)applicationWillTerminate:(UIApplication*)application {
   [CRIWV shutDown];
 }
 
 @end