Extend a Cargo CMS specific Javascript function

gistfile1.js

var openThisPrInline = (function() {
    // Store the existing function
    var oldFunction = window.openThisPrInline;

    // Return a new function
    return function(data) {
	// Run the old code
	oldFunction(data);

	// Start jScrollPane if #section-scroll exists
	if (document.getElementById("section-scroll")) { 
	    jQuery('#section-scroll').jScrollPane(); 
	} 
    };
})();