Prepare for computation of NewStructure in Resolution.

pkg/compiler/lib/src/elements/modelx.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 elements.modelx;
 
 import '../compiler.dart' show
     Compiler;
 import '../constants/constant_constructors.dart';
 import '../constants/constructors.dart';
@@ skipping 2307 matching lines @@
   int get hashCode => id;
 
   bool get hasBackendMembers => !backendMembers.isEmpty;
 
   bool get isUnnamedMixinApplication => false;
 
   @override
   bool get isEnumClass => false;
 
   InterfaceType computeType(Compiler compiler) {
-    if (thisTypeCache == null) {
+    if (isPatch) {
+      origin.computeType(compiler);
+      thisTypeCache = origin.thisType;
+      rawTypeCache = origin.rawType;
+    } else if (thisTypeCache == null) {
       computeThisAndRawType(compiler, computeTypeParameters(compiler));
     }
     return thisTypeCache;
   }
 
   void computeThisAndRawType(Compiler compiler, List<DartType> typeVariables) {
     if (thisTypeCache == null) {
       if (origin == null) {
         setThisAndRawTypes(compiler, typeVariables);
       } else {
@@ skipping 570 matching lines @@
   AstElement get definingElement;
 
   bool get hasResolvedAst => definingElement.hasTreeElements;
 
   ResolvedAst get resolvedAst {
     return new ResolvedAst(declaration,
         definingElement.node, definingElement.treeElements);
   }
 
 }