Add windows installer bot.

masters/master.client.dart/slaves.cfg

 # -*- python -*-
 # ex: set syntax=python:
 
 # Copyright (c) 2012 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 # See master.experimental/slaves.cfg for documentation.
 
 slaves = [
@@ skipping 125 matching lines @@
     'master': 'Dart',
     'builder': ['dart-editor',
                 'dart-editor-trunk'],
     'hostname': 'vm93-m3',
     'os': 'linux',
     'version': 'precise',
     'bits': '64',
   },
   {
     'master': 'Dart',
-    'builder': ['dart-editor-win', 'dart-editor-win-trunk'],
+    'builder': ['dart-editor-win', 'dart-editor-win-trunk',
+                'dart-editor-installer-win'],
     'hostname': 'vm128-m3',
     'os': 'win',
     'version': 'win7',
     'bits': '64',
   },
   {
     'master': 'Dart',
     'builder': ['dart-editor-installer-mac',
                 'dart-editor-mac',
                 'dart-editor-mac-trunk'],
@@ skipping 480 matching lines @@
           and not is_channel_builder(builder)):
         for channel in channel_postfixes:
           all_builders.append('%s%s' % (builder, channel))
       else:
         all_builders.append(builder)
     slave['builder'] = all_builders
   return slaves
 
 slaves = duplicate_builders_in_slaves(slaves)