code: function getLeftItemsWithVisibilityTrue() {
  			var aItems = [];
  			this.getItems().forEach(function (item) {
  				if (item instanceof sap.ui.commons.ToolbarSeparator || item.getVisible()) {
  					aItems.push(item);
  				}
  			});
  			return aItems;
  		}
docs: **************************************************************** Private functions **************************************************************** 
  Returns all items with API property visibility = true, including toolbar separator(s)
  @returns {Array} all items with API property visibility = true, including toolbar separator(s)
  @private