Git patches created by webkitpy now always have filename prefixes

third_party/WebKit/Tools/Scripts/webkitpy/common/checkout/scm/git.py

 # Copyright (c) 2009, 2010, 2011 Google Inc. All rights reserved.
 # Copyright (c) 2009 Apple Inc. All rights reserved.
 #
 # Redistribution and use in source and binary forms, with or without
 # modification, are permitted provided that the following conditions are
 # met:
 #
 #     * Redistributions of source code must retain the above copyright
 # notice, this list of conditions and the following disclaimer.
 #     * Redistributions in binary form must reproduce the above
@@ skipping 214 matching lines @@
 
         # Put code changes at the top of the patch and layout tests
         # at the bottom, this makes for easier reviewing.
         config_path = self._filesystem.dirname(self._filesystem.path_to_module('webkitpy.common.config'))
         order_file = self._filesystem.join(config_path, 'orderfile')
         order = ""
         if self._filesystem.exists(order_file):
             order = "-O%s" % order_file
 
         command = [self.executable_name, 'diff', '--binary', '--no-color', "--no-ext-diff",
-                   "--full-index", "--no-renames", order, self._merge_base(git_commit), "--"]
+                   "--full-index", "--no-renames", "--src-prefix=a/", "--dst-prefix=b/",
+                   order, self._merge_base(git_commit), "--"]
         if changed_files:
             command += changed_files
         return self._run(command, decode_output=False, cwd=self.checkout_root)
 
     @memoized
     def commit_position_from_git_commit(self, git_commit):
         git_log = self.git_commit_detail(git_commit)
         return self._commit_position_from_git_log(git_log)
 
     def checkout_branch(self, name):
@@ skipping 63 matching lines @@
         if self.current_branch() != self._branch_tracking_remote_master():
             return False
         if len(self._local_commits(self._branch_tracking_remote_master())) > 0:
             return False
         return True
 
     def ensure_cleanly_tracking_remote_master(self):
         self._discard_working_directory_changes()
         self._run_git(['checkout', '-q', self._branch_tracking_remote_master()])
         self._discard_local_commits()