Strong mode cleaning of many dart2js tests.

tests/compiler/dart2js/trust_type_annotations_test.dart

 // Copyright (c) 2014, 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 'package:expect/expect.dart';
 import "package:async_helper/async_helper.dart";
 import 'compiler_helper.dart';
 
 const String TEST = """
 class A {
@@ skipping 40 matching lines @@
   var compiler = compilerFor(TEST, uri, trustTypeAnnotations: true);
   asyncTest(() => compiler.run(uri).then((_) {
         var typesInferrer = compiler.globalInference.typesInferrerInternal;
         var closedWorld = typesInferrer.closedWorld;
 
         ClassElement classA = findElement(compiler, "A");
 
         checkReturn(String name, TypeMask type) {
           var element = classA.lookupMember(name);
           var mask = typesInferrer.getReturnTypeOfElement(element);
-          Expect.isTrue(type.containsMask(
-              typesInferrer.getReturnTypeOfElement(element), closedWorld));
+          Expect.isTrue(type.containsMask(mask, closedWorld));
         }
 
         checkType(String name, type) {
           var element = classA.lookupMember(name);
           Expect.isTrue(type.containsMask(
               typesInferrer.getTypeOfElement(element), closedWorld));
         }
 
         var intMask = new TypeMask.subtype(
             closedWorld.commonElements.intClass, closedWorld);
 
         checkReturn('foo', intMask);
         checkReturn('faa', intMask);
         checkType('aField', intMask);
         checkReturn('bar', intMask);
         checkReturn('baz', intMask);
         checkReturn('tear', intMask);
       }));
 }