new.target checks removal
In some classes extending GObject we are checking for new.target in _init which is always undefined, so replace it with this.constructor check instead.
Also use this for all the pure ES6 classes as it's more modern.
In some classes extending GObject we are checking for new.target in _init which is always undefined, so replace it with this.constructor check instead.
Also use this for all the pure ES6 classes as it's more modern.