code: function detectDocumentNavEnd(event) {
          if (event.keyCode === KeyEvent.DOM_VK_CONTROL) {  // Ctrl key
              MainViewManager.endTraversal();
              _addedNavKeyHandler = false;
              $(window.document.body).off("keyup", detectDocumentNavEnd);
          }
      }
docs: When the Ctrl key is released, if we were in the middle of a next/prev document navigation
  sequence, now is the time to end it and update the MRU order. If we allowed the order to update
  on every next/prev increment, the 1st & 2nd entries would just switch places forever and we'd
  never get further down the list.
  @param {jQueryEvent} event Key-up event