Revert of Notify the renderer if a history navigation has no subframe items.

content/renderer/render_frame_impl.h

Index: content/renderer/render_frame_impl.h
diff --git a/content/renderer/render_frame_impl.h b/content/renderer/render_frame_impl.h
index bdabfe2bbdb885289cb297cd18f1c04c4c2ed39a..9e07b358c83cfec218f18a5de9b43de7870fd873 100644
--- a/content/renderer/render_frame_impl.h
+++ b/content/renderer/render_frame_impl.h
@@ -1090,17 +1090,6 @@
   // didCreateDataSource().
   std::unique_ptr<NavigationParams> pending_navigation_params_;
 
-  // Keeps track of whether the browser process has any history items that need
-  // to be used for subframes of this frame (in the case of a history
-  // navigation).  If not, the renderer can skip sending an IPC to the browser
-  // and directly load any initial URLs for children itself.  This state is
-  // cleared during didStopLoading, since it is not needed after the first load
-  // completes and is never used after the initial navigation.  It is inherited
-  // by subframes.
-  // TODO(creis): Switch this to a data structure of unique names and
-  // corresponding same-process PageStates in https://crbug.com/639842.
-  bool browser_has_subtree_history_items_;
-
   // Stores the current history item for this frame, so that updates to it can
   // be reported to the browser process via SendUpdateState.
   blink::WebHistoryItem current_history_item_;