Use headless Chrome

Author: lenacohen

tests/selenium/pbtest.py

@@ -163,6 +163,7 @@ def on_travis(self):
     @contextmanager
     def chrome_manager(self):
         opts = ChromeOptions()
+        opts.add_argument("--headless")
         opts.add_argument("--load-extension=" + self.extension_path)
         opts.binary_location = self.browser_path