Error recovery broke host checked mode, fix it.

dart/pkg/compiler/lib/src/resolution/members.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.
 
 part of resolution;
 
 abstract class TreeElements {
   AnalyzableElement get analyzedElement;
   Iterable<Node> get superUses;
 
@@ skipping 4969 matching lines @@
   }
 }
 
 /// Looks up [name] in [scope] and unwraps the result.
 Element lookupInScope(Compiler compiler, Node node,
                       Scope scope, String name) {
   return Elements.unwrap(scope.lookup(name), compiler, node);
 }
 
 TreeElements _ensureTreeElements(AnalyzableElementX element) {
-  if (element.isErroneous) return new TreeElementMapping(element);
   if (element._treeElements == null) {
     element._treeElements = new TreeElementMapping(element);
   }
   return element._treeElements;
 }
 
 abstract class AnalyzableElementX implements AnalyzableElement {
   TreeElements _treeElements;
 
   bool get hasTreeElements => _treeElements != null;
@@ skipping 43 matching lines @@
 }
 
 /// The result for the resolution of the `assert` method.
 class AssertResult implements ResolutionResult {
   const AssertResult();
 
   Element get element => null;
 
   String toString() => 'AssertResult()';
 }