Reorganize dartdoc to new package layout.

pkg/dartdoc/lib/mirrors_util.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('mirrors.util');
 
+// TODO(rnystrom): Use "package:" URL (#4968).
 #import('mirrors.dart');
 #import('../../../lib/compiler/implementation/util/characters.dart');
 
 //------------------------------------------------------------------------------
 // Utility functions for using the Mirror API
 //------------------------------------------------------------------------------
 
 /**
  * Returns an iterable over the type declarations directly inheriting from
  * the declaration of this type.
@@ skipping 75 matching lines @@
   while (0 <= index && index < text.length) {
     var charCode = text.charCodeAt(index);
     if (charCode == $CR || charCode == $LF) {
       break;
     }
     index--;
     column++;
   }
   return column;
 }