Fix webkit_tests on Android

Because of https://codereview.chromium.org/401883007, webkit_tests was
failing with the stacktrace[1] below.

This patch attempts to fix that by adding in the extra (unused) argument to
android.py (which extends driver.py), mirroring the change to driver.py

[1]: http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Android%20%28Nexus4%29/builds/16591

The same problem[2] happened when the patch first landed[3], until it was
reverted[4].

[2]: http://build.chromium.org/p/chromium.webkit/builders/WebKit%20Android%20%28Nexus4%29/builds/16610
[3]: https://codereview.chromium.org/378113003
[4]: https://codereview.chromium.org/398543005

worker/1: TypeError('start() takes exactly 3 arguments (4 given)') raised:
    File "/b/build/slave/WebKit_Android__Nexus4_/build/src/third_party/WebKit/Tools/Scripts/webkitpy/common/message_pool.py", line 254, in run
      worker.handle(message.name, message.src, *message.args)
    File "/b/build/slave/WebKit_Android__Nexus4_/build/src/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/controllers/layout_test_runner.py", line 245, in handle
      device_failed = self._run_test(test_input, test_list_name)
    File "/b/build/slave/WebKit_Android__Nexus4_/build/src/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/controllers/layout_test_runner.py", line 288, in _run_test
      self._name, self._driver, test_input, stop_when_done)
    File "/b/build/slave/WebKit_Android__Nexus4_/build/src/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/controllers/single_test_runner.py", line 48, in run_single_test
      return runner.run()
    File "/b/build/slave/WebKit_Android__Nexus4_/build/src/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/controllers/single_test_runner.py", line 126, in run
      return self._run_compare_test()
    File "/b/build/slave/WebKit_Android__Nexus4_/build/src/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/controllers/single_test_runner.py", line 139, in _run_compare_test
      driver_output = self._driver.run_test(self._driver_input(), self._stop_when_done)
    File "/b/build/slave/WebKit_Android__Nexus4_/build/src/third_party/WebKit/Tools/Scripts/webkitpy/layout_tests/port/driver.py", line 154, in run_test
      self.start(driver_input.should_run_pixel_test, driver_input.args, stdin_deadline)

TBR=abarth@chromium.org,dpranke@chromium.org,thestig@chromium.org,ivandavid@chromium.org
NOTRY=true
NOTREECHECKS=true
BUG=388517

Review URL: https://codereview.chromium.org/401243005

git-svn-id: svn://svn.chromium.org/blink/trunk@178563 bbb929c8-8fbe-4397-9dbb-9b2b20218538