[ObjC ARC] Converts ios/chrome/browser/ui/ntp:ntp_internal to ARC.

ios/chrome/browser/ui/ntp/new_tab_page_view.mm

Index: ios/chrome/browser/ui/ntp/new_tab_page_view.mm
diff --git a/ios/chrome/browser/ui/ntp/new_tab_page_view.mm b/ios/chrome/browser/ui/ntp/new_tab_page_view.mm
index 5245ee5894f6f8217b6a0f9fed9161bb52973cc3..75aed942f79b7d82ff49ddf8c24160ca5c6f7684 100644
--- a/ios/chrome/browser/ui/ntp/new_tab_page_view.mm
+++ b/ios/chrome/browser/ui/ntp/new_tab_page_view.mm
@@ -5,20 +5,20 @@
 #import "ios/chrome/browser/ui/ntp/new_tab_page_view.h"
 
 #include "base/logging.h"
-#include "base/mac/objc_property_releaser.h"
 #import "ios/chrome/browser/ui/ntp/new_tab_page_bar.h"
 #import "ios/chrome/browser/ui/ntp/new_tab_page_bar_item.h"
 #import "ios/chrome/browser/ui/rtl_geometry.h"
 #include "ios/chrome/browser/ui/ui_util.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 @implementation NewTabPageView {
- @private
   // The objects pointed to by |tabBar_| and |scrollView_| are owned as
   // subviews already.
-  __unsafe_unretained NewTabPageBar* tabBar_;     // weak
-  __unsafe_unretained UIScrollView* scrollView_;  // weak
-
-  base::mac::ObjCPropertyReleaser propertyReleaser_NewTabPageView_;
+  __weak NewTabPageBar* tabBar_;
+  __weak UIScrollView* scrollView_;
 }
 
 @synthesize scrollView = scrollView_;
@@ -29,7 +29,6 @@
                     andTabBar:(NewTabPageBar*)tabBar {
   self = [super initWithFrame:frame];
   if (self) {
-    propertyReleaser_NewTabPageView_.Init(self, [NewTabPageView class]);
     [self addSubview:scrollView];
     [self addSubview:tabBar];
     scrollView_ = scrollView;