Handle deferred access as pre-step in SemanticSendVisitor.

pkg/compiler/lib/src/resolution/send_structure.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 dart2js.send_structure;
 
 import 'access_semantics.dart';
 import 'operators.dart';
 import 'semantic_visitor.dart';
 import '../dart_types.dart';
@@ skipping 2286 matching lines @@
                 arg);
         }
     }
     throw new SpannableAssertionFailure(node,
         "Invalid compound assigment: ${semantics}");
   }
 
   String toString() => 'postfix($operator,$semantics)';
 }
 
+
+/// The structure for a [Send] whose prefix is a prefix for a deferred library.
+/// For instance `deferred.a` where `deferred` is a deferred prefix.
+class DeferredPrefixStructure<R, A> implements SendStructure<R, A> {
+  /// The deferred prefix element.
+  final PrefixElement prefix;
+
+  /// The send structure for the whole [Send] node. For instance a
+  /// [GetStructure] for `deferred.a` where `a` is a top level member of the
+  /// deferred library.
+  final SendStructure sendStructure;
+
+  DeferredPrefixStructure(this.prefix, this.sendStructure) {
+    assert(sendStructure != null);
+  }
+
+  @override
+  R dispatch(SemanticSendVisitor<R, A> visitor, Send send, A arg) {
+    visitor.previsitDeferredAccess(send, prefix, arg);
+    return sendStructure.dispatch(visitor, send, arg);
+  }
+}
+
+
 /// The structure for a [NewExpression] of a new invocation.
 abstract class NewStructure<R, A> implements SemanticSendStructure<R, A> {
   /// Calls the matching visit method on [visitor] with [node] and [arg].
   R dispatch(SemanticSendVisitor<R, A> visitor, NewExpression node, A arg);
 }
 
 /// The structure for a [NewExpression] of a new invocation. For instance
 /// `new C()`.
 class NewInvokeStructure<R, A> extends NewStructure<R, A> {
   final ConstructorAccessSemantics semantics;
@@ skipping 313 matching lines @@
   ThisConstructorInvokeStructure(
       this.node, this.constructor, this.callStructure);
 
   R dispatch(SemanticDeclarationVisitor<R, A> visitor, A arg) {
     return visitor.visitThisConstructorInvoke(
         node, constructor, node.argumentsNode, callStructure, arg);
   }
 
   bool get isConstructorInvoke => true;
 }