[ChromeDriver] fix testCookieForFrame on Android

Remove creation of new ChromeDriver when testing Cookie retrieval for
frames to enable test to run on Android.

Bug: chromedriver:3396
Change-Id: If611001e2e72af95d96529872962703157563d7c
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2108904Reviewed-by: John Chen <johnchen@chromium.org>
Commit-Queue: Tricia Crichton <triciac@chromium.org>
Cr-Commit-Position: refs/heads/master@{#751487}

chrome/test/chromedriver/test/run_py_tests.py

@@ -1923,9 +1923,6 @@ class ChromeDriverTest(ChromeDriverBaseTestWithWebServer):
     self.assertEquals(0, len(self._driver.GetCookies()))
 
   def testCookieForFrame(self):
-    # Frame must have separate url than outer context for Cookies to be distinct
-    # the cross_domain_iframe with site-per-process fakes the needed setup
-    self._driver = self.CreateDriver(chrome_switches=['--site-per-process'])
     self._driver.Load(self.GetHttpUrlForFile(
         '/chromedriver/cross_domain_iframe.html'))
     self._driver.AddCookie({'name': 'outer', 'value': 'main context'})