[ObjC ARC] Converts ios/chrome/browser/ui/settings:unit_tests to ARC.

ios/chrome/browser/ui/settings/translate_collection_view_controller_unittest.mm

Index: ios/chrome/browser/ui/settings/translate_collection_view_controller_unittest.mm
diff --git a/ios/chrome/browser/ui/settings/translate_collection_view_controller_unittest.mm b/ios/chrome/browser/ui/settings/translate_collection_view_controller_unittest.mm
index 511ce28b2c5416b12f4bb02153e21fe9a0fd056f..34dad51cdeaf8c97bfd58c9f39ea9c27bf26bd08 100644
--- a/ios/chrome/browser/ui/settings/translate_collection_view_controller_unittest.mm
+++ b/ios/chrome/browser/ui/settings/translate_collection_view_controller_unittest.mm
@@ -27,6 +27,10 @@
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/base/l10n/l10n_util_mac.h"
 
+#if !defined(__has_feature) || !__has_feature(objc_arc)
+#error "This file requires ARC support."
+#endif
+
 using user_prefs::PrefRegistrySyncable;
 
 namespace {
@@ -43,7 +47,7 @@ class TranslateCollectionViewControllerTest
     pref_service_ = CreateLocalState();
   }
 
-  CollectionViewController* NewController() override NS_RETURNS_RETAINED {
+  CollectionViewController* InstantiateController() override {
     return [[TranslateCollectionViewController alloc]
         initWithPrefs:pref_service_.get()];
   }