constructor(ctrlKey, shiftKey, altKey, metaKey, keyCode) {
        this.ctrlKey = ctrlKey;
        this.shiftKey = shiftKey;
        this.altKey = altKey;
        this.metaKey = metaKey;
        this.keyCode = keyCode;
    }
Represents a chord which uses the `keyCode` field of keyboard events.
A chord is a combination of keys pressed simultaneously.