+x is bit 0, not 2. :(

patch.py

 # coding=utf8
 # Copyright (c) 2011 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.
 """Utility functions to handle patches."""
 
 import posixpath
 import os
 import re
 
@@ skipping 229 matching lines @@
         self._fail(
             'Confused %s from/to git diff for line %s.' %
                 (match.group(1), line))
       return
 
     # Handle "new file mode \d{6}"
     match = re.match(r'^new file mode (\d{6})$', line)
     if match:
       mode = match.group(1)
       # Only look at owner ACL for executable.
-      if bool(int(mode[4]) & 4):
+      if bool(int(mode[4]) & 1):
         self.svn_properties.append(('svn:executable', '*'))
 
     # Handle "--- "
     match = re.match(r'^--- (.*)$', line)
     if match:
       if last_line[:3] in ('---', '+++'):
         self._fail('--- and +++ are reversed')
       self.is_new = match.group(1) == '/dev/null'
       # TODO(maruel): Use self.source_file.
       if old != self.mangle(match.group(1)) and match.group(1) != '/dev/null':
@@ skipping 86 matching lines @@
     for patch in self.patches:
       patch.set_relpath(relpath)
 
   def __iter__(self):
     for patch in self.patches:
       yield patch
 
   @property
   def filenames(self):
     return [p.filename for p in self.patches]