Add the possibility to keep several version of the VS toolchain.

win_toolchain/package_from_installed.py

 # 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.
 
 """
 From a system-installed copy of the toolchain, packages all the required bits
 into a .zip file.
 
 It assumes default install locations for tools, in particular:
 - C:\Program Files (x86)\Microsoft Visual Studio 12.0\...
@@ skipping 230 matching lines @@
   old_dir = os.getcwd()
   os.chdir(tempdir)
   if VS_VERSION == '2013':
     rel_dir = 'vs2013_files'
   else:
     rel_dir = 'vs_files'
   with zipfile.ZipFile(
       os.path.join(old_dir, output), 'r', zipfile.ZIP_DEFLATED, True) as zf:
     zf.extractall(rel_dir)
   print 'Hashing...'
-  sha1 = get_toolchain_if_necessary.CalculateHash(rel_dir)
+  sha1 = get_toolchain_if_necessary.CalculateHash(rel_dir, None)
   os.chdir(old_dir)
   shutil.rmtree(tempdir)
   final_name = sha1 + '.zip'
   os.rename(output, final_name)
   print 'Renamed %s to %s.' % (output, final_name)
 
 
 def main():
   usage = 'usage: %prog [options] 2013|2015'
   parser = optparse.OptionParser(usage)
@@ skipping 59 matching lines @@
   sys.stdout.write('\rWrote to %s.%s\n' % (output, ' '*50))
   sys.stdout.flush()
 
   RenameToSha1(output)
 
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main())