Format all tests.

tests/language/super_mixin_test.dart

Index: tests/language/super_mixin_test.dart
diff --git a/tests/language/super_mixin_test.dart b/tests/language/super_mixin_test.dart
index 8263a1b6bd926c3b6f53e73998392d8fe8f0c0dd..154d3e5719b31988873d8b951878145fd3fd0f3d 100644
--- a/tests/language/super_mixin_test.dart
+++ b/tests/language/super_mixin_test.dart
@@ -12,9 +12,7 @@ class Mixin {
   get getter => 42;
 }
 
-class Superclass {
-
-}
+class Superclass {}
 
 class Subclass extends Superclass with Mixin {
   method() => super.getter;
@@ -22,4 +20,4 @@ class Subclass extends Superclass with Mixin {
 
 void main() {
   Expect.equals(42, new Subclass().method());
-}
+}