Element no longer implements AnalysisTarget

pkg/analyzer/lib/src/context/cache.dart

 // Copyright (c) 2015, 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.context.cache;
 
 import 'dart:async';
 import 'dart:collection';
 
 import 'package:analyzer/src/generated/engine.dart';
@@ skipping 912 matching lines @@
   void put(CacheEntry entry) {
     AnalysisTarget target = entry.target;
     if (entry._partition != null) {
       throw new StateError(
           'The entry for $target is already in ${entry._partition}');
     }
     entry._partition = this;
     entry.fixExceptionState();
     if (target is ElementImpl) {
       // Detect attempts to mutate the map key.
-      target.frozen = true;
+      (target as ElementImpl).frozen = true;

[Brian Wilkerson, 2016/02/01 15:43:20]

Seem like this change should be moved back to the CL that adds the field
"frozen" in case we commit one but not the other.

     }
     entryMap[target] = entry;
     _addIfSource(target);
   }
 
   /**
    * Remove all information related to the given [target] from this partition.
    * Return the entry associated with the target, or `null` if there was cache
    * entry for the target.
    */
@@ skipping 318 matching lines @@
   void resultAccessed(TargetedResult result) {}
 
   @override
   List<TargetedResult> resultStored(TargetedResult newResult, newValue) {
     return TargetedResult.EMPTY_LIST;
   }
 
   @override
   void targetRemoved(AnalysisTarget target) {}
 }