Revert of Display content_shell error messages.

third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/driver.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 314 matching lines @@
         self._current_cmd_line = cmd_line
 
         if wait_for_ready:
             deadline = time.time() + DRIVER_START_TIMEOUT_SECS
             if not self._wait_for_server_process_output(self._server_process, deadline, '#READY'):
                 _log.error("content_shell took too long to startup.")
 
     def _wait_for_server_process_output(self, server_process, deadline, text):
         output = ''
         line = server_process.read_stdout_line(deadline)
-        output += server_process.pop_all_buffered_stderr()
         while not server_process.timed_out and not server_process.has_crashed() and not text in line.rstrip():
             output += line
             line = server_process.read_stdout_line(deadline)
-            output += server_process.pop_all_buffered_stderr()
 
         if server_process.timed_out or server_process.has_crashed():
             _log.error('Failed to start the %s process: \n%s', server_process.name(), output)
             return False
 
         return True
 
     def _run_post_start_tasks(self):
         # Remote drivers may override this to delay post-start tasks until the server has ack'd.
         if self._profiler:
@@ skipping 196 matching lines @@
         self.decoded_content = None
         self.malloc = None
         self.js_heap = None
         self.stdin_path = None
 
     def decode_content(self):
         if self.encoding == 'base64' and self.content is not None:
             self.decoded_content = base64.b64decode(self.content)
         else:
             self.decoded_content = self.content