Add Youtube auto play integration test

tools/chrome_proxy/webdriver/video.py

Index: tools/chrome_proxy/webdriver/video.py
diff --git a/tools/chrome_proxy/webdriver/video.py b/tools/chrome_proxy/webdriver/video.py
index ead67e1180fad729a67483a357380c1f0ff41629..c080b8b0c864d9c05a8ec9c53853f19900a71397 100644
--- a/tools/chrome_proxy/webdriver/video.py
+++ b/tools/chrome_proxy/webdriver/video.py
@@ -7,6 +7,7 @@ import time
 import common
 from common import TestDriver
 from common import IntegrationTest
+from common import NotAndroid
 
 
 class Video(IntegrationTest):
@@ -117,5 +118,17 @@ class Video(IntegrationTest):
       if metrics['failed']:
         raise Exception('Test failed!')
 
+  # Make sure YouTube autoplays.
+  @NotAndroid
+  def testYoutube(self):
+    with TestDriver() as t:
+      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()