Dynamically add/remove backdropClass

[weilinzung]

Currently, there is no way we can dynamically add/remove backdropClass with a condition. It looks like once backDropClass is added, there is no way we can remove it.

addBg() {
this.satPopover.backdropClass = 'test';
}

changeBg() {
this.satPopover.backdropClass = 'test2';
}


removeBg() {
this.satPopover.backdropClass = ''; => replace to empty?
}