Restore lazy parsing of classes.

dart/lib/dartdoc/mirrors/dart2js_mirror.dart

 // Copyright (c) 2012, 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('mirrors.dart2js');
 
 #import('../../compiler/compiler.dart', prefix: 'diagnostics');
 #import('../../compiler/implementation/elements/elements.dart');
 #import('../../compiler/implementation/apiimpl.dart', prefix: 'api');
 #import('../../compiler/implementation/scanner/scannerlib.dart');
@@ skipping 481 matching lines @@
   }
 
   String qualifiedName() => simpleName();
 
   void _ensureTypes() {
     if (_types == null) {
       _types = <InterfaceMirror>{};
       _library.forEachExport((Element e) {
         if (e.getLibrary() == _library) {
           if (e.isClass()) {
+            e.ensureResolved(system.compiler);
             var type = new Dart2JsInterfaceMirror.fromLibrary(this, e);
             _types[type.canonicalName] = type;
           } else if (e.isTypedef()) {
             var type = new Dart2JsTypedefMirror.fromLibrary(this, e);
             _types[type.canonicalName] = type;
           }
         }
       });
     }
   }
@@ skipping 850 matching lines @@
     if (node !== null) {
       var span = system.compiler.spanFromNode(node, script.uri);
       return new Dart2JsLocation(script, span);
     } else {
       var span = system.compiler.spanFromElement(_variable);
       return new Dart2JsLocation(script, span);
     }
   }
 }