Force to disable slimming paint on Android when running layout tests

Tools/Scripts/webkitpy/layout_tests/port/android.py

 # Copyright (C) 2012 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 1048 matching lines @@
             stdout.encode('utf8', 'replace'),
             stderr.encode('utf8', 'replace'),
             newer_than)
 
     def cmd_line(self, pixel_tests, per_test_args):
         # The returned command line is used to start _server_process. In our case, it's an interactive 'adb shell'.
         # The command line passed to the driver process is returned by _driver_cmd_line() instead.
         return self._android_commands.adb_command() + ['shell']
 
     def _android_driver_cmd_line(self, pixel_tests, per_test_args):
-        return driver.Driver.cmd_line(self, pixel_tests, per_test_args)
+        # FIXME: We can't enable slimming paint before crbug.com/439457 is fixed.
+        cmd_line = driver.Driver.cmd_line(self, pixel_tests, per_test_args)
+        if '--enable-slimming-paint' in cmd_line:
+            _log.warning('Android port doesn\'t support slimming paint because of crbug.com/439457')
+            cmd_line.remove('--enable-slimming-paint')
+        return cmd_line
 
     @staticmethod
     def _loop_with_timeout(condition, timeout_secs):
         deadline = time.time() + timeout_secs
         while time.time() < deadline:
             if condition():
                 return True
         return False
 
     def _all_pipes_created(self):
@@ skipping 206 matching lines @@
         return command
 
     def _read_prompt(self, deadline):
         last_char = ''
         while True:
             current_char = self._server_process.read_stdout(deadline, 1)
             if current_char == ' ':
                 if last_char in ('#', '$'):
                     return
             last_char = current_char