Use WorldImpact for element dependencies in deferred_load

pkg/compiler/lib/src/dart_backend/backend.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 dart_backend;
 
 // TODO(ahe): This class is simply wrong.  This backend should use
 // elements when it can, not AST nodes.  Perhaps a [Map<Element,
 // TreeElements>] is what is needed.
 class ElementAst {
@@ skipping 343 matching lines @@
     return false;
   }
 }
 
 class DartResolutionCallbacks extends ResolutionCallbacks {
   final DartBackend backend;
 
   DartResolutionCallbacks(this.backend);
 
   @override
-  WorldImpact transformImpact(ResolutionWorldImpact worldImpact) {
+  WorldImpact transformImpact(ResolutionImpact worldImpact) {
     TransformedWorldImpact transformed =
         new TransformedWorldImpact(worldImpact);
     for (DartType typeLiteral in worldImpact.typeLiterals) {
       if (typeLiteral.isInterfaceType) {
         backend.usedTypeLiterals.add(typeLiteral.element);
       }
     }
     for (InterfaceType instantiatedType in worldImpact.instantiatedTypes) {
       // TODO(johnniwinther): Remove this when dependency tracking is done on
       // the world impact itself.
@@ skipping 181 matching lines @@
   }
 
   // TODO(johnniwinther): Remove this when values are computed from the
   // expressions.
   @override
   void copyConstantValues(DartConstantTask task) {
     constantCompiler.constantValueMap.addAll(
         task.constantCompiler.constantValueMap);
   }
 }