Enable support to remove the executable bit on the CQ.

patch.py

 # coding=utf8
 # Copyright (c) 2012 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 373 matching lines @@
     if match:
       # It is necessary to parse it because there may be no hunk, like when the
       # file was empty.
       self.is_delete = True
       return
 
     match = re.match(r'^new(| file) mode (\d{6})$', line)
     if match:
       mode = match.group(2)
       # Only look at owner ACL for executable.
-      # TODO(maruel): Add support to remove a property.
       if bool(int(mode[4]) & 1):
         self.svn_properties.append(('svn:executable', '*'))
+      else:
+        self.svn_properties.append(('svn:executable', None))
       return
 
     match = re.match(r'^--- (.*)$', line)
     if match:
       if last_line[:3] in ('---', '+++'):
         self._fail('--- and +++ are reversed')
       if match.group(1) == '/dev/null':
         self.is_new = True
       elif self.mangle(match.group(1)) != old:
         # git patches are always well formatted, do not allow random filenames.
@@ skipping 98 matching lines @@
   def __iter__(self):
     for patch in self.patches:
       yield patch
 
   def __getitem__(self, key):
     return self.patches[key]
 
   @property
   def filenames(self):
     return [p.filename for p in self.patches]