Added integration test to Chrome Proxy to verify direct connection on remote site timeout

tools/chrome_proxy/integration_tests/chrome_proxy_measurements.py

Index: tools/chrome_proxy/integration_tests/chrome_proxy_measurements.py
diff --git a/tools/chrome_proxy/integration_tests/chrome_proxy_measurements.py b/tools/chrome_proxy/integration_tests/chrome_proxy_measurements.py
index 7c05b9517ef276252dfb6421111ff10ac04a47e0..c5a53c784d292b62cd2645b07102322c8f8b35e3 100644
--- a/tools/chrome_proxy/integration_tests/chrome_proxy_measurements.py
+++ b/tools/chrome_proxy/integration_tests/chrome_proxy_measurements.py
@@ -13,6 +13,26 @@ from metrics import loading
 from telemetry.core import exceptions, util
 from telemetry.page import page_test
 
+BLACKHOLE_SERVER_URL = 'http://blackhole-1470152441488.appspot.com'
+
+class ChromeProxyClientBypassOnTimeout(ChromeProxyValidation):
+  """Tests that client bypasses proxy after proxy timeouts on HTTP
+  response.
+  """
+
+  def __init__(self):
+    super(ChromeProxyClientBypassOnTimeout, self).__init__(
+        restart_after_each_page=True,
+        metrics=metrics.ChromeProxyMetric())
+
+  def CustomizeBrowserOptions(self, options):
+    super(ChromeProxyClientBypassOnTimeout, self).CustomizeBrowserOptions(options)

[bustamante, 2016/08/03 21:40:55]

Nit - this line is over 80 characters, and should be split.

[Robert Ogden, 2016/08/08 16:46:41]

Done.

+    self._is_chrome_proxy_enabled = False
+    options.AppendExtraBrowserArgs('--data-reduction-proxy-http-proxies='
+        + BLACKHOLE_SERVER_URL)
+
+  def AddResults(self, tab, results):
+    self._metrics.AddResultsForClientBypassOnTimeout(tab, results)
 
 class ChromeProxyDataSaving(page_test.PageTest):
   """Chrome proxy data saving measurement."""
@@ -677,4 +697,4 @@ class ChromeProxyPingback(ChromeProxyValidation):
       '--enable-stats-collection-bindings')
 
   def AddResults(self, tab, results):
-    self._metrics.AddResultsForPingback(tab, results)
+    self._metrics.AddResultsForPingback(tab, results)