Format all tests.

tests/language/assert_message_test.dart

Index: tests/language/assert_message_test.dart
diff --git a/tests/language/assert_message_test.dart b/tests/language/assert_message_test.dart
index 28499edb0474faf31ae844491256e73937e3bad7..38c5d315b326c0bd04e2352505e1a03caf3a703b 100644
--- a/tests/language/assert_message_test.dart
+++ b/tests/language/assert_message_test.dart
@@ -67,10 +67,11 @@ main() {
   }
 
   asyncStart();
-  asyncTests().then((_) { asyncEnd(); });
+  asyncTests().then((_) {
+    asyncEnd();
+  });
 }
 
-
 Future asyncTests() async {
   // You can await in both condition and message.
   assert(true, await 0);