Run dartfmt on all files under runtime.

runtime/observatory/tests/service/issue_27287_test.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 file.
 // VMOptions=--error_on_bad_type --error_on_bad_override  --verbose_debug
 
 import 'service_test_common.dart';
 import 'test_helper.dart';
 import 'dart:developer';
 
 const int LINE_A = 17;
 const int LINE_B = 18;
 
 var libVariable;
 
 testMain() {
   debugger();
-  print("Before");  // LINE_A
-  libVariable = 0;  // LINE_B
+  print("Before"); // LINE_A
+  libVariable = 0; // LINE_B
   print("and after");
 }
 
 var tests = [
   hasStoppedAtBreakpoint,
   stoppedAtLine(LINE_A),
   stepOver,
   // Check that debugger stops at assignment to top-level variable.
   stoppedAtLine(LINE_B),
   resumeIsolate,
 ];
 
 main(args) => runIsolateTests(args, tests, testeeConcurrent: testMain);