Switch docs to path package (away from dart:io Path).

tools/dom/docs/lib/docs.dart

 // Copyright (c) 2013, 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.
 
 /**
  * A library for extracting the documentation from the various HTML libraries
  * ([dart:html], [dart:svg], [dart:web_audio], [dart:indexed_db]) and saving
  * those documentation comments to a JSON file.
  */
 
@@ skipping 33 matching lines @@
  *             ...
  *           }
  *         },
  *         ...
  *       },
  *       ...
  *     }
  *
  * Completes to `true` if any errors were encountered, `false` otherwise.
  */
-Future<bool> convert(Path libPath, Path jsonPath) {
-  var paths = <Path>[];
+Future<bool> convert(String libPath, String jsonPath) {
+  var paths = <String>[];
   for (var libraryName in HTML_LIBRARY_NAMES) {
-    paths.add(new Path(libraryName));
+    paths.add(libraryName);
   }
 
   return analyze(paths, libPath, options: ['--preserve-comments'])
     .then((MirrorSystem mirrors) {
       var convertedJson = _generateJsonFromLibraries(mirrors);
       return _exportJsonToFile(convertedJson, jsonPath);
     });
 }
 
-Future<bool> _exportJsonToFile(Map convertedJson, Path jsonPath) {
+Future<bool> _exportJsonToFile(Map convertedJson, String jsonPath) {
   return new Future.sync(() {
-    final jsonFile = new File.fromPath(jsonPath);
+    final jsonFile = new File(jsonPath);
     var writeJson = prettySerialize(convertedJson);
 
     var outputStream = jsonFile.openWrite();
     outputStream.writeln(writeJson);
     outputStream.close();
     return outputStream.done.then((_) => false);
   });
 }
 
 Map _generateJsonFromLibraries(MirrorSystem mirrors) {
@@ skipping 105 matching lines @@
     for (var s in tags.reflectee.split(',')) {
       domNames.add(s.trim());
     }
 
     if (domNames.length == 1 && domNames[0] == 'none') return <String>[];
     return domNames;
   } else {
     return <String>[];
   }
 }