Format all multitests

tests/language_strong/const_objects_are_immutable_test.dart

Index: tests/language_strong/const_objects_are_immutable_test.dart
diff --git a/tests/language_strong/const_objects_are_immutable_test.dart b/tests/language_strong/const_objects_are_immutable_test.dart
index 8028818d2af3d00f7dbab202717e065d14a68ba3..3daa082084a72789b0259eb8a27bdda56af01cea 100644
--- a/tests/language_strong/const_objects_are_immutable_test.dart
+++ b/tests/language_strong/const_objects_are_immutable_test.dart
@@ -15,7 +15,7 @@ main() {
   Expect.throws(() => list[0] = 3);
   Expect.equals(1, list[0]);
 
-  var m = const { 'foo': 499 };
+  var m = const {'foo': 499};
   Expect.throws(() => m['foo'] = 42);
   Expect.equals(499, m['foo']);