[Telemetry] Remove logic of pulling out user_agent_type from page_set

telemetry/telemetry/page/shared_page_state.py

Index: telemetry/telemetry/page/shared_page_state.py
diff --git a/telemetry/telemetry/page/shared_page_state.py b/telemetry/telemetry/page/shared_page_state.py
index cd76d894462562258d2ae174134783b43a89b781..45c6506de500f152187c645a3e3ffb2f070d6f8f 100644
--- a/telemetry/telemetry/page/shared_page_state.py
+++ b/telemetry/telemetry/page/shared_page_state.py
@@ -58,19 +58,7 @@ class SharedPageState(story.SharedState):
       self._test = timeline_based_page_test.TimelineBasedPageTest(test)
     else:
       self._test = test
-    device_type = self._device_type
-    # TODO(aiolos, nednguyen): Remove this logic of pulling out user_agent_type
-    # from story_set once all page_set are converted to story_set
-    # (crbug.com/439512).
-
-    def _IsPageSetInstance(s):
-      # This is needed to avoid importing telemetry.page.page_set which will
-      # cause cyclic import.
-      return 'PageSet' == s.__class__.__name__ or 'PageSet' in (
-          list(c.__name__ for c in s.__class__.__bases__))
-    if not device_type and _IsPageSetInstance(story_set):
-      device_type = story_set.user_agent_type
-    _PrepareFinderOptions(finder_options, self._test, device_type)
+    _PrepareFinderOptions(finder_options, self._test, self._device_type)
     self._browser = None
     self._finder_options = finder_options
     self._possible_browser = self._GetPossibleBrowser(