Move dart2js from sdk/lib/_internal/compiler to pkg/compiler

pkg/compiler/lib/src/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
@@ skipping 2473 matching lines @@
     if (element is PartialElement) {
       PartialElement partial = element as PartialElement;
       partial.hasParseError = true;
     }
     return new ErrorNode(element.position, e.reason);
   }
   Node node = listener.popNode();
   assert(listener.nodes.isEmpty);
   return node;
 }