Run formatter on a few frontend and kernel files that hadn't been formatted.

pkg/front_end/testcases/rasta/super_operator.dart

 // Copyright (c) 2016, 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.md file.
 
 class A {
-  operator + (String s) => null;
+  operator +(String s) => null;
 
-  operator [] (i) => null;
+  operator [](i) => null;
 
-  operator []= (i, val) {}
+  operator []=(i, val) {}
 }
 
 class B extends A {
-  operator + (String s) => super + ("${s}${s}");
+  operator +(String s) => super + ("${s}${s}");
 
-  operator [] (i) => super[i];
+  operator [](i) => super[i];
 
-  operator []= (i, val) => super[i++] += val;
+  operator []=(i, val) => super[i++] += val;
 }
 
 class Autobianchi {
   g() => super[0];
 }