Removed all analyzer issues from tests

runtime/observatory/tests/service/evaluate_activation_in_method_class_other.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.
 
 import 'dart:developer';
 
 var topLevel = "OtherLibrary";
 
 class Superclass {
   var _instVar = 'Superclass';
   var instVar = 'Superclass';
   method() => 'Superclass';
   static staticMethod() => 'Superclass';
+  suppress_warning() => _instVar;
 }
 
 class Klass extends Superclass {
   var _instVar = 'Klass';
   var instVar = 'Klass';
   method() => 'Klass';
   static staticMethod() => 'Klass';
 
   test() {
     var _local = 'Klass';
     debugger();
+    // Suppress unused variable warning.
+    print(_local);
   }
 }