pkg/compiler: fix imports

pkg/compiler/lib/src/serialization/resolved_ast_serialization.dart

 // Copyright (c) 2016, 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.serialization.resolved_ast;
 
 import '../common.dart';
 import '../common/resolution.dart';
 import '../constants/expressions.dart';
 import '../dart_types.dart';
 import '../diagnostics/diagnostic_listener.dart';
 import '../elements/elements.dart';
 import '../elements/modelx.dart';
 import '../parser/listener.dart' show ParserError;
 import '../parser/node_listener.dart' show NodeListener;
 import '../parser/parser.dart' show Parser;
 import '../resolution/enum_creator.dart';
 import '../resolution/send_structure.dart';
 import '../resolution/tree_elements.dart';
 import '../tokens/token.dart';
 import '../tree/tree.dart';
 import '../universe/selector.dart';
 import '../util/util.dart';
 import 'keys.dart';
 import 'modelz.dart';
 import 'serialization.dart';
 import 'serialization_util.dart';
-import 'modelz.dart';
 
 /// Visitor that computes a node-index mapping.
 class AstIndexComputer extends Visitor {
   final Map<Node, int> nodeIndices = <Node, int>{};
   final List<Node> nodeList = <Node>[];
 
   @override
   visitNode(Node node) {
     nodeIndices.putIfAbsent(node, () {
       // Some nodes (like Modifier and empty NodeList) can be reused.
@@ skipping 649 matching lines @@
         }
       }
     }
     element.resolvedAst =
         new ParsedResolvedAst(element, root, body, elements, uri);
   }
 }
 
 const Key PARAMETER_NODE = const Key('parameter.node');
 const Key PARAMETER_INITIALIZER = const Key('parameter.initializer');