code: function appendKeyBindingString(element, keyBindingString) {
  		var span = document.createElement("span"); //$NON-NLS-0$
  		span.classList.add("dropdownKeyBinding"); //$NON-NLS-0$
  		span.appendChild(document.createTextNode(keyBindingString));
  		element.appendChild(span);
  	}
docs: Appends the specified keyBindingString to the specified menu item.
  @param {Object} element The menu item to append the keybinding string to. Required.
  @param {String} keyBindingString The keybinding string to append. Required.