[chromedriver] Load the automation extension as a component extension.

chrome/test/chromedriver/test/run_py_tests.py

Index: chrome/test/chromedriver/test/run_py_tests.py
diff --git a/chrome/test/chromedriver/test/run_py_tests.py b/chrome/test/chromedriver/test/run_py_tests.py
index 2b01b5af6712f83b9dff3fac7a5a74340c430611..70c3b69e242b521cd60b3e47bef0a53936c7e320 100755
--- a/chrome/test/chromedriver/test/run_py_tests.py
+++ b/chrome/test/chromedriver/test/run_py_tests.py
@@ -707,8 +707,7 @@ class ExistingBrowserTest(ChromeDriverBaseTest):
     if process is None:
       raise RuntimeError('Chrome could not be started with debugging port')
     try:
-      hostAndPort = '127.0.0.1:%d' % port
-      driver = self.CreateDriver(chrome_existing_browser=hostAndPort)
+      driver = self.CreateDriver(debugger_address='127.0.0.1:%d' % port)
       driver.ExecuteScript('console.info("%s")' % 'connecting at %d!' % port)
       driver.Quit()
     finally: