Add script to generate winrt headers using cppwinrt.exe (#442)

* Add script to generate winrt headers using cppwinrt.exe

* Fix script

Author: clarkezone

build/win/generate_winrt_headers.py

@@ -0,0 +1,42 @@
+#!/usr/bin/env python
+# Copyright 2014 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.
+
+import os
+import shutil
+import subprocess
+import sys
+
+def clean(output_dir):
+  if os.path.exists(output_dir):
+        shutil.rmtree(output_dir, ignore_errors=True)
+  return
+
+
+def generate_headers(output_dir):
+  """Run cppwinrt.exe on the installed Windows SDK version and generate
+  cppwinrt headers in the output directory.
+  """
+  
+  cppwinrt_exe = os.path.join(
+  __file__,
+  '..\\..\\..\\third_party\\cppwinrt\\bin\\cppwinrt.exe')
+
+  args = [cppwinrt_exe, '-in', 'sdk',
+      '-out', '%s' % output_dir]
+
+  subprocess.check_output(args)
+
+  return 0
+
+
+def main(argv):
+  generated_dir = os.path.join(
+  __file__,
+  '..\\..\\..\\third_party\\cppwinrt\\generated')
+  clean(generated_dir)
+  return generate_headers(generated_dir)
+
+if __name__ == "__main__":
+  sys.exit(main(sys.argv[1:]))