Add GetResponses() and related funcionality

tools/chrome_proxy/webdriver/simple_smoke.py

Index: tools/chrome_proxy/webdriver/simple_smoke.py
diff --git a/tools/chrome_proxy/webdriver/simple_smoke.py b/tools/chrome_proxy/webdriver/simple_smoke.py
index c07b44778dad8f6bf30a20ecc5d8800b42ea058d..f1e537e2760ebffad365c35965733b4b688d3fb3 100644
--- a/tools/chrome_proxy/webdriver/simple_smoke.py
+++ b/tools/chrome_proxy/webdriver/simple_smoke.py
@@ -18,6 +18,10 @@ class SimpleSmoke(IntegrationTest):
       t.LoadPage()
       print 'Document Title: ', t.ExecuteJavascript('document.title')
       time.sleep(5)
+      responses = t.GetHTTPResponses()
+      for response in responses:
+        print "URL: %s, ViaHeader: %s, XHR: %s" % (response.url,
+          response.ResponseHasViaHeader(), response.WasXHR())
 
 if __name__ == '__main__':
   test = SimpleSmoke()