[ObjC ARC] Converts ios/chrome/app/application_delegate:application_delegate_internal to ARC.

ios/chrome/app/application_delegate/app_state.h

 // Copyright 2016 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.
 
 #ifndef IOS_CHROME_APP_APPLICATION_DELEGATE_APP_STATE_H_
 #define IOS_CHROME_APP_APPLICATION_DELEGATE_APP_STATE_H_
 
 #import <UIKit/UIKit.h>
 
 @protocol AppNavigation;
@@ skipping 19 matching lines @@
      startupInformation:(id<StartupInformation>)startupInformation
     applicationDelegate:(MainApplicationDelegate*)applicationDelegate
     NS_DESIGNATED_INITIALIZER;
 
 // YES if the user has ever interacted with the application. May be NO if the
 // application has been woken up by the system for background work.
 @property(nonatomic, readonly) BOOL userInteracted;
 
 // Window for the application, it is not set during the initialization method.
 // Set the property before calling methods related to it.
-@property(nonatomic, assign) UIWindow* window;
+@property(nonatomic, weak) UIWindow* window;
 
 // Saves the launchOptions to be used from -newTabFromLaunchOptions. If the
 // application is in background, initialize the browser to basic. If not, launch
 // the browser.
 // Returns whether additional delegate handling should be performed (call to
 // -performActionForShortcutItem or -openURL by the system for example)
 - (BOOL)requiresHandlingAfterLaunchWithOptions:(NSDictionary*)launchOptions
                                stateBackground:(BOOL)stateBackground;
 
 // Whether the application is in Safe Mode.
@@ skipping 31 matching lines @@
                          appNavigation:(id<AppNavigation>)appNavigation;
 
 // Sets the return value for -didFinishLaunchingWithOptions that determines if
 // UIKit should make followup delegate calls such as
 // -performActionForShortcutItem or -openURL.
 - (void)launchFromURLHandled:(BOOL)URLHandled;
 
 @end
 
 #endif  // IOS_CHROME_APP_APPLICATION_DELEGATE_APP_STATE_H_