Fix bugs found in checked mode.

tests/compiler/dart2js/parser_helper.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.
 
 #library('parser_helper');
 
 #import("dart:uri");
 
 #import("../../../lib/compiler/implementation/elements/elements.dart");
 #import("../../../lib/compiler/implementation/tree/tree.dart");
@@ skipping 16 matching lines @@
 
 Node parseBodyCode(String text, Function parseMethod) {
   Token tokens = scan(text);
   LoggerCanceler lc = new LoggerCanceler();
   Script script =
       new Script(
           new Uri.fromComponents(scheme: "source"),
           new MockFile(text));
   LibraryElement library = new LibraryElement(script);
   library.canUseNative = true;
-  NodeListener listener = new NodeListener(lc, library);
+  NodeListener listener = new NodeListener(lc, library.entryCompilationUnit);
   Parser parser = new Parser(listener);
   Token endToken = parseMethod(parser, tokens);
   assert(endToken.kind == EOF_TOKEN);
   Node node = listener.popNode();
   Expect.isNotNull(node);
   Expect.isTrue(listener.nodes.isEmpty(), 'Not empty: ${listener.nodes}');
   return node;
 }
 
 Node parseStatement(String text) =>
@@ skipping 26 matching lines @@
   compiler.withCurrentElement(unit, () => parser.parseUnit(tokens));
   return unit.localMembers;
 }
 
 // TODO(ahe): We define this method to avoid having to import
 // the scanner in the tests. We should move SourceString to another
 // location instead.
 SourceString buildSourceString(String name) {
   return new SourceString(name);
 }