recent_topics: Fix partially hidden row sometimes in recent topics.

The top row of the RT can be hidden sometimes after scrolling down
and then scrolling up. This is because the focus is applied before
the row is rendered. Applying the focus after the topic row is
rendered by the browser makes sure it is always visisble when
it needs to be.

static/js/recent_topics.js

@@ -66,7 +66,10 @@ function set_table_focus(row, col) {
         return true;
     }
 
+    // Setting focus after the render is complete doesn't partially hide the row from view.
+    setTimeout(() => {
         topic_rows.eq(row).find(".recent_topics_focusable").eq(col).children().trigger("focus");
+    }, 0);
     current_focus_elem = "table";
     return true;
 }