anchor.diff:      // class A {
       //   get g {}
       // }
  -    LibraryElementImpl library =
  -        ElementFactory.library(createAnalysisContext(), "lib");
  +    LibraryElementImpl library = _newLibrary();
       ClassElementImpl classA = ElementFactory.classElement2("A");
       String getterName = "g";
       PropertyAccessorElement getter =
  
positive.code:   void test_lookUpSetter_undeclared() {
      // class A {
      // }
      LibraryElementImpl library =
          ElementFactory.library(createAnalysisContext(), "lib");
      ClassElementImpl classA = ElementFactory.classElement2("A");
      (library.definingCompilationUnit as CompilationUnitElementImpl).types =
          <ClassElement>[classA];
  
negative.code:     // }
      // class B extends A {
      // }
      LibraryElementImpl library = _newLibrary();
      ClassElementImpl classA = ElementFactory.classElement2("A");
      String methodName = "m";
      MethodElement inheritedMethod =
  