Converts ios/chrome/browser/native_app_launcher:native_app_launcher_internal to ARC.

ios/chrome/browser/native_app_launcher/native_app_navigation_util.mm

 // Copyright 2017 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.
 
 #include "ios/chrome/browser/native_app_launcher/native_app_navigation_util.h"
 
 #include "base/logging.h"
 #include "ios/web/public/navigation_item.h"
 #include "ios/web/public/navigation_manager.h"
 #import "ios/web/public/web_state/web_state.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 namespace native_app_launcher {
 
 bool IsLinkNavigation(web::WebState* web_state) {
   web::NavigationManager* navigationManager = web_state->GetNavigationManager();
   DCHECK(navigationManager);
   int index = navigationManager->GetCurrentItemIndex();
   // Walks backward on the navigation items list looking for the first item
   // that is not the result of a redirect. Check if user arrived at that
   // via link click or a suggestion on the UI.
   while (index >= 0) {
     web::NavigationItem* item = navigationManager->GetItemAtIndex(index);
     DCHECK(item);
     ui::PageTransition currentTransition = item->GetTransitionType();
     // Checks non-redirect entries for transitions that are either links or
     // bookmarks.
     if ((currentTransition & ui::PAGE_TRANSITION_IS_REDIRECT_MASK) == 0) {
       return PageTransitionCoreTypeIs(currentTransition,
                                       ui::PAGE_TRANSITION_LINK) ||
              PageTransitionCoreTypeIs(currentTransition,
                                       ui::PAGE_TRANSITION_AUTO_BOOKMARK);
     }
     --index;
   }
   return false;
 }
 
 }  // namespace native_app_launcher