Format all tests.

tests/language_strong/checked_mode_helper.dart

Index: tests/language_strong/checked_mode_helper.dart
diff --git a/tests/language_strong/checked_mode_helper.dart b/tests/language_strong/checked_mode_helper.dart
index 695222da755f57d923f5d991f1902eeaa5ea670b..72ad80af7845f4d54761b265eda07978f962cbc3 100644
--- a/tests/language_strong/checked_mode_helper.dart
+++ b/tests/language_strong/checked_mode_helper.dart
@@ -33,11 +33,10 @@ void checkDynamicTypeError(f(), [String message]) {
   message = message != null ? ': $message' : '';
   try {
     f();
-    Expect.isFalse(inCheckedMode(),
-      'Missing type error in checked mode$message.');
+    Expect.isFalse(
+        inCheckedMode(), 'Missing type error in checked mode$message.');
   } on TypeError catch (e) {
-    Expect.isTrue(inCheckedMode(),
-      'Unexpected type error in production mode.');
+    Expect.isTrue(inCheckedMode(), 'Unexpected type error in production mode.');
   }
 }