Don't have svn ls block waiting for password

win_toolchain/get_toolchain_if_necessary.py

 #!/usr/bin/env python
 # Copyright 2013 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.
 
 """Downloads and unpacks a toolchain for building on Windows. The contents are
 matched by sha1 which will be updated when the toolchain is updated.
 
 Having a toolchain script in depot_tools means that it's not versioned
 directly with the source code. That is, if the toolchain is upgraded, but
@@ skipping 103 matching lines @@
     'sha1': sha1,
   }
   with open(MakeTimestampsFileName(root), 'wb') as f:
     json.dump(timestamps_data, f)
 
 
 def HaveSrcInternalAccess():
   """Checks whether access to src-internal is available."""
   with open(os.devnull, 'w') as nul:
     if subprocess.call(
-        ['svn', 'ls',
+        ['svn', 'ls', '--non-interactive',
          'svn://svn.chromium.org/chrome-internal/trunk/src-internal/'],
         shell=True, stdin=nul, stdout=nul, stderr=nul) == 0:
       return True
     return subprocess.call(
         ['git', 'remote', 'show',
          'https://chrome-internal.googlesource.com/chrome/src-internal/'],
         shell=True, stdin=nul, stdout=nul, stderr=nul) == 0
 
 
 def DelayBeforeRemoving(target_dir):
@@ skipping 61 matching lines @@
 
   if options.output_json:
     shutil.copyfile(os.path.join(target_dir, '..', 'data.json'),
                     options.output_json)
 
   return 0
 
 
 if __name__ == '__main__':
   sys.exit(main())