Made helpers strong-mode clean for Dart 2.0 migration.

tests/lib_strong/mirrors/declarations_model_easier.dart

 // Copyright (c) 2013, 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 test.declarations_model;
 
 var libraryVariable;
 get libraryGetter => null;
 set librarySetter(x) => x;
 libraryMethod() => null;
@@ skipping 26 matching lines @@
   static get inheritedStaticGetter => null;
   static set inheritedStaticSetter(x) => x;
   static inheritedStaticMethod() => null;
 
   Superclass.inheritedGenerativeConstructor(this.inheritedInstanceVariable);
   Superclass.inheritedRedirectingConstructor(x)
       : this.inheritedGenerativeConstructor(x * 2);
   factory Superclass.inheritedNormalFactory(y) =>
       new Superclass.inheritedRedirectingConstructor(y * 3);
   factory Superclass.inheritedRedirectingFactory(z) =
-      Superclass.inheritedNormalFactory;
+      Superclass<S>.inheritedNormalFactory;
 }
 
 abstract class Class<C> extends Superclass<C> implements Interface<C> {
   operator +(x) => null;
 
   abstractMethod();
 
   var instanceVariable;
   get instanceGetter => null;
   set instanceSetter(x) => x;
   instanceMethod() => null;
 
   static var staticVariable;
   static get staticGetter => null;
   static set staticSetter(x) => x;
   static staticMethod() => null;
 
   Class.generativeConstructor(this.instanceVariable)
       : super.inheritedGenerativeConstructor(0);
   Class.redirectingConstructor(x) : this.generativeConstructor(x * 2);
   factory Class.normalFactory(y) => new ConcreteClass(y * 3);
-  factory Class.redirectingFactory(z) = Class.normalFactory;
+  factory Class.redirectingFactory(z) = Class<C>.normalFactory;
 }
 
 // This is just here as a target of Class's factories to appease the analyzer.
 class ConcreteClass<CC> extends Class<CC> {
   abstractMethod() {}
 
   operator /(x) => null;
 
   var interfaceInstanceVariable;
   get interfaceInstanceGetter => null;
   set interfaceInstanceSetter(x) => null;
   interfaceInstanceMethod() => null;
 
   ConcreteClass(x) : super.generativeConstructor(x);
 }