Fix tests

Author: GaryQian

lib/ui/hooks.dart

@@ -50,7 +50,7 @@ _LocaleClosure _getLocaleClosure() => _localeClosure;
 @pragma('vm:entry-point')
 void _updateLocales(List<String> locales) {
   final int stringsPerLocale = 4;
-  int numLocales = (locales.length / stringsPerLocale).toInt();
+  int numLocales = locales.length ~/ stringsPerLocale;
   window._locales = new List<Locale>(numLocales);
   for (int localeIndex = 0; localeIndex < numLocales; localeIndex++) {
     window._locales[localeIndex] = new Locale(locales[localeIndex * stringsPerLocale],

testing/dart/window_hooks_integration_test.dart

@@ -100,7 +100,7 @@ void main() {
         };
       });
 
-      _updateLocale('en', 'US', '', '');
+      _updateLocales(<String>['en', 'US', '', '']);
       expect(runZone, isNotNull);
       expect(runZone, same(innerZone));
       expect(locale, equals(const Locale('en', 'US')));