Revert "Parts must start with 'part of'" and "Attempt to fix VM build"

dart/lib/compiler/implementation/scanner/listener.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 scanner;
-
 const bool VERBOSE = false;
 
 /**
  * A parser event listener that does nothing except throw exceptions
  * on parser errors.
  */
 class Listener {
   void beginArgumentDefinitionTest(Token token) {
   }
 
@@ skipping 1894 matching lines @@
 
 Node parse(DiagnosticListener diagnosticListener,
            CompilationUnitElement element,
            doParse(Parser parser)) {
   NodeListener listener = new NodeListener(diagnosticListener, element);
   doParse(new Parser(listener));
   Node node = listener.popNode();
   assert(listener.nodes.isEmpty());
   return node;
 }