Start adding support for mixin application syntax. We now parse the typedef variant of mixin applic…

sdk/lib/_internal/compiler/implementation/dart_backend/utils.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;
 
 class CloningVisitor implements Visitor<Node> {
   final TreeElements originalTreeElements;
   final TreeElementMapping cloneTreeElements;
 
@@ skipping 99 matching lines @@
       visit(node.typeArguments), visit(node.entries), node.constKeyword);
 
   visitLiteralMapEntry(LiteralMapEntry node) => new LiteralMapEntry(
       visit(node.key), node.colonToken, visit(node.value));
 
   visitLiteralNull(LiteralNull node) => new LiteralNull(node.token);
 
   visitLiteralString(LiteralString node) => new LiteralString(
       node.token, node.dartString);
 
+  visitMixinApplication(MixinApplication node) => new MixinApplication(
+      visit(node.modifiers), visit(node.superclass), visit(node.mixins),
+      node.beginToken, node.endToken);
+
   visitModifiers(Modifiers node) => new Modifiers(visit(node.nodes));
 
   visitNamedArgument(NamedArgument node) => new NamedArgument(
       visit(node.name), node.colonToken, visit(node.expression));
 
   visitNewExpression(NewExpression node) => new NewExpression(
       node.newToken, visit(node.send));
 
   rewriteNodeList(NodeList node, Link link) =>
       new NodeList(node.beginToken, link, node.endToken, node.delimiter);
@@ skipping 142 matching lines @@
   }
 
   Node visitStringNode(StringNode node) {
     unimplemented('visitNode', node: node);
   }
 
   unimplemented(String message, {Node node}) {
     throw message;
   }
 }