Move serving_dirs to UserStorySet, update user_story_runner.

tools/telemetry/telemetry/page/__init__.py

Index: tools/telemetry/telemetry/page/__init__.py
diff --git a/tools/telemetry/telemetry/page/__init__.py b/tools/telemetry/telemetry/page/__init__.py
index 673a0f129caf63bd66ece5aaa6cd0142c5b31c3e..7cd7894346036031d7ecea2b21e270370b1c1a53 100644
--- a/tools/telemetry/telemetry/page/__init__.py
+++ b/tools/telemetry/telemetry/page/__init__.py
@@ -200,7 +200,3 @@ class Page(user_story.UserStory):
     all_urls = [p.url.rstrip('/') for p in self.page_set if p.is_file]
     common_prefix = os.path.dirname(os.path.commonprefix(all_urls))
     return self.url[len(common_prefix):].strip('/')
-
-  @property
-  def archive_path(self):
-    return self.page_set.WprFilePathForUserStory(self)