Re-land "Format all multitests"

tests/language/mixin_supertype_subclass3_test.dart

Index: tests/language/mixin_supertype_subclass3_test.dart
diff --git a/tests/language/mixin_supertype_subclass3_test.dart b/tests/language/mixin_supertype_subclass3_test.dart
index 584e4443c0036d82110eb7e16487d28159276221..c1893fe2addccb34e804069602815ebf6c1928a1 100644
--- a/tests/language/mixin_supertype_subclass3_test.dart
+++ b/tests/language/mixin_supertype_subclass3_test.dart
@@ -14,17 +14,22 @@
 // In this test, M is declared as `class M = S_static with G;`.
 
 class B {}
+
 class C {}
+
 class D {}
+
 class E extends B with C implements D {}
+
 class F extends E {}
+
 class A
   = E with M; class M = B with G; class G //# 01: ok
   = E with M; class M = C with G; class G //# 02: static type warning
   = E with M; class M = D with G; class G //# 03: ok
   = E with M; class M = E with G; class G //# 04: ok
   = E with M; class M = F with G; class G //# 05: static type warning
-  {}
+{}
 
 main() {
   new A();