Rev the version of apache ant in third_party to 1.8.4. This will fix an issue with

tools/create_editor.py

 #!/usr/bin/env python
 #
 # 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 script which will be invoked from gyp to create a build of the editor.
 # 
 # TODO(devoncarew): currently this script is not callable from tools/build.py
 # Usage: ./tools/build.py editor
@@ skipping 18 matching lines @@
   'linux': 'linux, gtk',
   'macos': 'macosx, cocoa'
 }
 
 ARCH_CONFIG = {
   'ia32': 'x86',
   'x64': 'x86_64'
 }
 
 def AntPath():
-  parent = join('third_party', 'apache_ant', 'v1_7_1', 'bin')
+  parent = join('third_party', 'apache_ant', '1.8.4', 'bin')
   if utils.IsWindows():
     return join(parent, 'ant.bat')
   else:
     return join(parent, 'ant')
 
 
 def ProcessEditorArchive(archive, outDir):
   tempDir = join(GetEditorTemp(), 'editor.out')
   os.makedirs(tempDir)
 
@@ skipping 135 matching lines @@
     ProcessEditorArchive(archives[0], OUTPUT)
 
   if os.path.exists(GetEditorTemp()):
     shutil.rmtree(GetEditorTemp())
 
   print('\nEditor build successful')
 
 
 if __name__ == '__main__':
   sys.exit(Main())