Refactor decorators into thier own python class

tools/chrome_proxy/webdriver/video.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 time
 
 import common
 from common import TestDriver
 from common import IntegrationTest
-from common import NotAndroid
+from decorators import NotAndroid
 
 
 class Video(IntegrationTest):
 
   # Check videos are proxied.
   def testCheckVideoHasViaHeader(self):
     with TestDriver() as t:
       t.AddChromeArg('--enable-spdy-proxy-auth')
       t.LoadURL(
         'http://check.googlezip.net/cacheable/video/buck_bunny_tiny.html')
@@ skipping 109 matching lines @@
       t.AddChromeArg('--enable-spdy-proxy-auth')
       t.LoadURL('http://data-saver-test.appspot.com/youtube')
       t.WaitForJavascriptExpression(
         'window.playerState == YT.PlayerState.PLAYING', 30)
       for response in t.GetHTTPResponses():
         if not response.url.startswith('https'):
           self.assertHasChromeProxyViaHeader(response)
 
 if __name__ == '__main__':
   IntegrationTest.RunAllTests()