Fixes to mock SDK to enable dart:core to be summarized.

pkg/analyzer/lib/src/generated/testing/element_factory.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.
 
 library analyzer.src.generated.testing.element_factory;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/element/element.dart';
 import 'package:analyzer/dart/element/type.dart';
@@ skipping 383 matching lines @@
         new FunctionTypeImpl.forTypedef(functionTypeAliasElement);
     return functionTypeAliasElement;
   }
 
   static PropertyAccessorElementImpl getterElement(
       String name, bool isStatic, DartType type) {
     FieldElementImpl field = new FieldElementImpl(name, -1);
     field.static = isStatic;
     field.synthetic = true;
     field.type = type;
+    field.final2 = true;
     PropertyAccessorElementImpl getter =
         new PropertyAccessorElementImpl.forVariable(field);
+    getter.synthetic = false;
     getter.getter = true;
     getter.variable = field;
     getter.returnType = type;
     field.getter = getter;
     FunctionTypeImpl getterType = new FunctionTypeImpl(getter);
     getter.type = getterType;
     return getter;
   }
 
   static ImportElementImpl importFor(
@@ skipping 195 matching lines @@
   }
 
   static TypeParameterElementImpl typeParameterWithType(String name,
       [DartType bound]) {
     TypeParameterElementImpl typeParameter = typeParameterElement(name);
     typeParameter.type = new TypeParameterTypeImpl(typeParameter);
     typeParameter.bound = bound;
     return typeParameter;
   }
 }