Format all tests.

tests/language_strong/stacktrace_test.dart

Index: tests/language_strong/stacktrace_test.dart
diff --git a/tests/language_strong/stacktrace_test.dart b/tests/language_strong/stacktrace_test.dart
index e39f151c8bd8d12bbacc01bd65ff7bdfbe29887e..20ddcb003a33fa8ddacb9b1fc1a100be61e56dc4 100644
--- a/tests/language_strong/stacktrace_test.dart
+++ b/tests/language_strong/stacktrace_test.dart
@@ -1,4 +1,3 @@
-
 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
@@ -11,7 +10,7 @@ void main() {
   var ex = new Exception("fail");
   try {
     throw ex;
-  } on Exception catch(e, st) {
+  } on Exception catch (e, st) {
     Expect.equals(ex, e);
     Expect.isTrue(st.toString().endsWith("\n"));
   }