Strong mode cleaning of many dart2js tests.

tests/compiler/dart2js/source_map_name_test.dart

 // Copyright (c) 2015, 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.
 
 library source_map_name_test;
 
 import 'package:async_helper/async_helper.dart';
 import 'package:expect/expect.dart';
 import 'package:compiler/src/compiler.dart';
 import 'package:compiler/src/elements/elements.dart';
@@ skipping 86 matching lines @@
       }
       Expect.isNotNull(element, "Element '$name' not found.");
       return element;
     }
 
     void checkName(String expectedName,
         [List<String> expectedClosureNames, String lookupName]) {
       if (lookupName == null) {
         lookupName = expectedName;
       }
-      var element = lookup(lookupName);
+      dynamic element = lookup(lookupName);
       check(element, expectedName);
       if (element.isConstructor) {
         var constructorBody =
             element.enclosingClass.lookupConstructorBody(element.name);
         Expect.isNotNull(
             element, "Constructor body '${element.name}' not found.");
         check(constructorBody, expectedName);
       }
 
       if (expectedClosureNames != null) {
@@ skipping 29 matching lines @@
     checkName('Class.instanceAnonymous',
         ['Class.instanceAnonymous.<anonymous function>']);
     checkName('Class.instanceLocal', ['Class.instanceLocal.localMethod']);
     checkName('Class.instanceNestedLocal', [
       'Class.instanceNestedLocal.localMethod',
       'Class.instanceNestedLocal.localMethod.<anonymous function>',
       'Class.instanceNestedLocal.localMethod.nestedLocalMethod'
     ]);
   });
 }