hashchange: Remove hiding of recent topics.

Recent Topics is hidden when we switch to a narrow view
or the All Messages view, so this call is not needed.
It will also become actively unhelpful when we build
a stream-specific recent topics page, because then it
will be possible to have a hash change that shouldn't
close the recent topics view.

web/src/hashchange.js

@@ -95,7 +95,6 @@ export function changehash(newhash) {
     if (browser_history.state.changing_hash) {
         return;
     }
-    maybe_hide_recent_topics();
     message_viewport.stop_auto_scrolling();
     set_hash(newhash);
 }