Add CoreTypes interface.

pkg/compiler/lib/src/mirrors/dart2js_instance_mirrors.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.
 
 part of dart2js.mirrors;
 
 abstract class ObjectMirrorMixin implements ObjectMirror {
   InstanceMirror getField(Symbol fieldName) {
     throw new UnsupportedError('ObjectMirror.getField unsupported.');
   }
@@ skipping 66 matching lines @@
   String toString() {
     if (_constant != null) {
       return _constant.getText();
     } else {
       return _value.unparse();
     }
   }
 
   ClassMirror get type {
     return mirrorSystem._getTypeDeclarationMirror(
-        _value.computeType(mirrorSystem.compiler).element);
+        _value.getType(mirrorSystem.compiler.coreTypes).element);
   }
 
   int get hashCode => 13 * _constant.hashCode;
 
   bool operator ==(var other) {
     if (other is! Dart2JsConstantMirror) return false;
     return _value == other._value;
   }
 }
 
@@ skipping 195 matching lines @@
       return new Dart2JsBoolConstantMirror.fromBool(mirrorSystem, isDocComment);
     } else if (fieldName == #text) {
       return new Dart2JsStringConstantMirror.fromString(mirrorSystem, text);
     } else if (fieldName == #trimmedText) {
       return new Dart2JsStringConstantMirror.fromString(mirrorSystem,
                                                         trimmedText);
     }
     return super.getField(fieldName);
   }
 }