Remove unused Lite Page fallback code

tools/chrome_proxy/webdriver/lite_page.py

 # Copyright 2017 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import common
 from common import TestDriver
 from common import IntegrationTest
 
 import time
 
@@ skipping 71 matching lines @@
       self.assertGreater(new_scroll_height, original_scroll_height)
 
       # Make sure there were more requests that were proxied.
       responses = test_driver.GetHTTPResponses(override_has_logs=True)
       self.assertNotEqual(0, len(responses))
       for response in responses:
         self.assertHasChromeProxyViaHeader(response)
         self.assertIn(response.status, [200, 204])
 
   # Lo-Fi fallback is not currently supported via the client. Check that
-  # no Lo-Fi response is received if the user is in the
-  # DataCompressionProxyLitePageFallback field trial and a Lite Page is not
-  # served.
+  # no Lo-Fi response is received if a Lite Page is not served.
   def testLitePageFallback(self):
     with TestDriver() as test_driver:
       test_driver.AddChromeArg('--enable-spdy-proxy-auth')
       test_driver.AddChromeArg('--force-fieldtrials='
-                               'DataCompressionProxyLoFi/Enabled_Preview/'
-                               'DataCompressionProxyLitePageFallback/Enabled')
+                               'DataCompressionProxyLoFi/Enabled_Preview/')
       test_driver.AddChromeArg('--force-fieldtrial-params='
                                'DataCompressionProxyLoFi.Enabled_Preview:'
                                'effective_connection_type/4G')
       test_driver.AddChromeArg('--force-net-effective-connection-type=2g')
 
       test_driver.LoadURL('http://check.googlezip.net/lite-page-fallback')
 
       lite_page_requests = 0
       lo_fi_responses = 0
       for response in test_driver.GetHTTPResponses():
@@ skipping 12 matching lines @@
 
         # Lo-Fi fallback is not currently supported via the client. Check that
         # no Lo-Fi response is received.
         self.checkLoFiResponse(response, False)
 
       # Verify that a Lite Page was requested.
       self.assertEqual(1, lite_page_requests)
 
 if __name__ == '__main__':
   IntegrationTest.RunAllTests()