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

tools/chrome_proxy/integration_tests/chrome_proxy_metrics.py

Index: tools/chrome_proxy/integration_tests/chrome_proxy_metrics.py
diff --git a/tools/chrome_proxy/integration_tests/chrome_proxy_metrics.py b/tools/chrome_proxy/integration_tests/chrome_proxy_metrics.py
index 9c12daa1c4781d54ce840f90646d562c81ff11c0..dc1b8f9799721fd9c75f99f68e89eb841915a420 100644
--- a/tools/chrome_proxy/integration_tests/chrome_proxy_metrics.py
+++ b/tools/chrome_proxy/integration_tests/chrome_proxy_metrics.py
@@ -872,6 +872,25 @@ class ChromeProxyMetric(network_metrics.NetworkMetric):
     results.AddValue(scalar.ScalarValue(
         results.current_page, 'succeeded_sum', 'count', succeeded))
 
+  def AddResultsForClientBypassOnTimeout(self, tab, results):
+    bypass_count = 0
+    via_count = 0
+    tab.WaitForDocumentReadyStateToBeComplete(timeout=30)
+    for resp in self.IterResponses(tab):
+      if resp.HasChromeProxyViaHeader():
+        via_count += 1

[bustamante, 2016/08/03 19:04:39]

You probably don't need to keep track of via_count since this will throw an
exception if it ever gets incremented, so the value won't be available anyways.

[Robert Ogden, 2016/08/03 21:12:32]

Done.

+        r = resp.response
+        raise ChromeProxyMetricException, (
+            'Response for %s should not have via header after proxy timeout.\n'
+            'Reponse: status=(%d, %s)\nHeaders:\n %s' % (
+                r.url, r.status, r.status_text, r.headers))
+      else:
+        bypass_count += 1
+    results.AddValue(scalar.ScalarValue(

[bustamante, 2016/08/03 19:04:39]

It's worth adding a check to verify that bypass_count > 0, so this doesn't pass
if there aren't any requests at all.

[Robert Ogden, 2016/08/03 21:12:32]

Done.

+        results.current_page, 'bypass', 'count', bypass_count))
+    results.AddValue(scalar.ScalarValue(
+        results.current_page, 'via', 'count', via_count))
+
 PROXIED = 'proxied'
 DIRECT = 'direct'