Fix build to create Windows SDK.

tools/build.py

 #!/usr/bin/env python
 #
 # Copyright (c) 2011, 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.
 #
 
 import optparse
 import os
 import shutil
@@ skipping 104 matching lines @@
                 build_config,
                 'SYMROOT=%s' % os.path.abspath('xcodebuild')
                 ]
       elif HOST_OS == 'win32':
         project_file = 'dart.sln'
         if os.path.exists('dart-%s.gyp' % CurrentDirectoryBaseName()):
           project_file = 'dart-%s.sln' % CurrentDirectoryBaseName()
         args = [options.devenv + os.sep + 'devenv.com',
                 '/build',
                 build_config,
+                '/project',
+                target,
                 project_file
                ]
       else:
         make = 'make'
         if HOST_OS == 'freebsd':
           make = 'gmake'
           # work around lack of flock
           os.environ['LINK'] = '$(CXX)'
         args = [make,
                 '-j',
@@ skipping 16 matching lines @@
       process.wait()
       if process.returncode != 0:
         print "BUILD FAILED"
         return 1
 
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(Main())