More changes to support hermetic Xcode toolchain in GN.

chrome/tools/build/mac/copy_keystone_framework.py

 # Copyright 2016 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 os.path
 import shutil
 import subprocess
 import sys
 
 # Usage: python copy_keystone_framework.py /path/to/input /path/to/output
+#        [DEVELOPER_DIR]
 #
 # This script copies the KeystoneRegistration.framework, removing its
 # versioned directory structure, thinning it to just x86_64, and deleting
 # the Headers directory.
 
 def Main(args):
-  if len(args) != 3:
+  if len(args) != 3 and len(args) != 4:
     print >> sys.stderr, '%s: /path/to/input /path/to/output' % (args[0],)
     return 1
+  if len(args) == 4:
+    os.environ['DEVELOPER_DIR'] = args[3]
 
   # Delete any old copies of the framework.
   output_path = os.path.join(args[2], 'KeystoneRegistration.framework')
   if os.path.exists(output_path):
     shutil.rmtree(output_path)
 
   # Copy the framework out of its versioned directory. Use rsync to exclude
   # dotfiles and the Headers directories.
   subprocess.check_call(
       ['rsync', '-acC', '--delete',
        '--exclude', 'Headers', '--exclude', 'PrivateHeaders',
        '--include', '*.so',
        os.path.join(args[1], 'Versions/Current/'),
        output_path])
 
   # Thin the library to just the required arch.
   library_path = os.path.join(output_path, 'KeystoneRegistration')
   subprocess.check_call(
       ['lipo', '-thin', 'x86_64', library_path, '-o', library_path])
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(Main(sys.argv))