Make msvs-ninja work for target_arch=x64

pylib/gyp/__init__.py

 #!/usr/bin/env python
 
 # Copyright (c) 2012 Google Inc. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import copy
 import gyp.input
 import optparse
 import os.path
@@ skipping 475 matching lines @@
   # twice)
   for format in set(options.formats):
     params = {'options': options,
               'build_files': build_files,
               'generator_flags': generator_flags,
               'cwd': os.getcwd(),
               'build_files_arg': build_files_arg,
               'gyp_binary': sys.argv[0],
               'home_dot_gyp': home_dot_gyp,
               'parallel': options.parallel,
-              'root_targets': options.root_targets}
+              'root_targets': options.root_targets,
+              'target_arch': cmdline_default_variables.get('target_arch', '')}
 
     # Start with the default variables from the command line.
     [generator, flat_list, targets, data] = Load(
         build_files, format, cmdline_default_variables, includes, options.depth,
         params, options.check, options.circular_check)
 
     # TODO(mark): Pass |data| for now because the generator needs a list of
     # build files that came in.  In the future, maybe it should just accept
     # a list, and not the whole data dict.
     # NOTE: flat_list is the flattened dependency graph specifying the order
@@ skipping 19 matching lines @@
   except GypError, e:
     sys.stderr.write("gyp: %s\n" % e)
     return 1
 
 # NOTE: setuptools generated console_scripts calls function with no arguments
 def script_main():
   return main(sys.argv[1:])
 
 if __name__ == '__main__':
   sys.exit(script_main())