dist/event-target-shim.js
function setCancelFlag(data) {
    if (data.passiveListener != null) {
        if (
            typeof console !== "undefined" &&
            typeof console.error === "function"
        ) {
            console.error(
                "Unable to preventDefault inside passive event listener invocation.",
                data.passiveListener
            );
        }
        return
    }
    if (!data.event.cancelable) {
        return
    }

    data.canceled = true;
    if (typeof data.event.preventDefault === "function") {
        data.event.preventDefault();
    }
}
function setCancelFlag(data) {
    if (data.passiveListener != null) {
        if (
            typeof console !== "undefined" &&
            typeof console.error === "function"
        ) {
            console.error(
                "Unable to preventDefault inside passive event listener invocation.",
                data.passiveListener
            );
        }
        return
    }
    if (!data.event.cancelable) {
        return
    }

    data.canceled = true;
    if (typeof data.event.preventDefault === "function") {
        data.event.preventDefault();
    }
}
function setCancelFlag ( data ) { if ( data . passiveListener != null ) { if ( typeof console !== "undefined" && typeof console . error === "function" ) { console . error ( "Unable to preventDefault inside passive event listener invocation." , data . passiveListener ) ; } return } if ( ! data . event . cancelable ) { return } data . canceled = true ; if ( typeof data . event . preventDefault === "function" ) { data . event . preventDefault ( ) ; } }
https://dom.spec.whatwg.org/#set-the-canceled-flag
@param data {PrivateData} private data.
https : // dom . spec . whatwg . org / #set - the - canceled - flag