Introduce WPTServe for running W3C Blink Layout tests

Tools/Scripts/webkitpy/layout_tests/servers/server_base.py

 # Copyright (C) 2011 Google 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
 # copyright notice, this list of conditions and the following disclaimer
@@ skipping 54 matching lines @@
 
         # Subclasses must override these fields.
         self._name = '<virtual>'
         self._log_prefixes = tuple()
         self._mappings = {}
         self._pid_file = None
         self._start_cmd = None
 
         # Subclasses may override these fields.
         self._env = None
+        self._cwd = None
         self._stdout = self._executive.PIPE
         self._stderr = self._executive.PIPE
         self._process = None
         self._pid = None
         self._error_log_path = None
 
     def start(self):
         """Starts the server. It is an error to start an already started server.
 
         This method also stops any stale servers started by a previous instance."""
@@ skipping 70 matching lines @@
         delete the logs will actually cause start() to fail."""
         # Sometimes logs are open in other processes but they should clear eventually.
         for log_prefix in self._log_prefixes:
             try:
                 self._remove_log_files(self._output_dir, log_prefix)
             except OSError, e:
                 _log.warning('Failed to remove old %s %s files' % (self._name, log_prefix))
 
     def _spawn_process(self):
         _log.debug('Starting %s server, cmd="%s"' % (self._name, self._start_cmd))
-        process = self._executive.popen(self._start_cmd, env=self._env, stdout=self._stdout, stderr=self._stderr)
-        pid = process.pid
+        self._process = self._executive.popen(self._start_cmd,
+                                              env=self._env,
+                                              cwd=self._cwd,
+                                              stdout=self._stdout,
+                                              stderr=self._stderr)
+        pid = self._process.pid
         self._filesystem.write_text_file(self._pid_file, str(pid))
         return pid
 
     def _stop_running_server(self):
         self._wait_for_action(self._check_and_kill)
         if self._filesystem.exists(self._pid_file):
             self._filesystem.remove(self._pid_file)
 
     def _check_and_kill(self):
         if self._executive.check_running_pid(self._pid):
@@ skipping 92 matching lines @@
             except IOError, e:
                 if e.errno in (errno.EALREADY, errno.EADDRINUSE):
                     raise ServerError('Port %d is already in use.' % port)
                 elif self._platform.is_win() and e.errno in (errno.WSAEACCES,):  # pylint: disable=E1101
                     raise ServerError('Port %d is already in use.' % port)
                 else:
                     raise
             finally:
                 s.close()
         _log.debug('all ports are available')