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

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

Index: ios/chrome/browser/ui/ntp/new_tab_page_egtest.mm
diff --git a/ios/chrome/browser/ui/ntp/new_tab_page_egtest.mm b/ios/chrome/browser/ui/ntp/new_tab_page_egtest.mm
index 384447094e146cbcde58d9b24882ba84364863fe..15b433eaffd7f1efcfae0e777f9f77f19453de95 100644
--- a/ios/chrome/browser/ui/ntp/new_tab_page_egtest.mm
+++ b/ios/chrome/browser/ui/ntp/new_tab_page_egtest.mm
@@ -20,6 +20,10 @@
 #import "ios/testing/wait_util.h"
 #include "ui/base/l10n/l10n_util.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 @implementation NewTabPageController (ExposedForTesting)
 - (GoogleLandingController*)googleLandingController {
   return googleLandingController_;
@@ -73,8 +77,8 @@ void SelectNewTabPagePanel(NewTabPage::PanelIdentifier panel_type) {
       tag = IDC_SHOW_OTHER_DEVICES;
     }
     if (tag) {
-      base::scoped_nsobject<GenericChromeCommand> command(
-          [[GenericChromeCommand alloc] initWithTag:tag]);
+      GenericChromeCommand* command =
+          [[GenericChromeCommand alloc] initWithTag:tag];
       chrome_test_util::RunCommandWithActiveViewController(command);
     }
   }