Format all tests.

tests/language/generic_field_mixin_test.dart

Index: tests/language/generic_field_mixin_test.dart
diff --git a/tests/language/generic_field_mixin_test.dart b/tests/language/generic_field_mixin_test.dart
index 267a8b71136bcb29809f0412ac5a837ab2e11ccb..ea34a9e2d0eb7258cfa3274f7e8d4c14ad8aeb9a 100644
--- a/tests/language/generic_field_mixin_test.dart
+++ b/tests/language/generic_field_mixin_test.dart
@@ -9,7 +9,9 @@ import 'package:expect/expect.dart';
 class M<T> {
   var field = new A<T>();
 }
+
 class A<U> {}
+
 class C1<V> = Object with M<V>;
 class C2 = Object with M<int>;
 class C3 = Object with M<String>;
@@ -25,4 +27,4 @@ main() {
 
   Expect.isFalse(new C3().field is A<int>);
   Expect.isTrue(new C3().field is A<String>);
-}
+}