DEV: Upgrade Ember to 3.15 and remove jQuery and lodash as dependencies

[OsamaSayegh]

No description provided.

[OsamaSayegh]

This decorator is a small experiment I did that I'd like someone to review. It solves the problem where we have a component method used as an event handler that we need to later remove when the component is destroyed, and we want this inside the method to refer to the component and not the DOM element the event is attached to.

Currently I'm doing this:

endDrag() {
  if (this._endDrag) return this._endDrag;

  const handler = () => {
    this.set("clicked", true);
    console.log("Element clicked!");
  };
  this.set("_endDrag", handler);
  return this._endDrag;
}

and in didInsertElement:

document.addEventListener("click", this.endDrag());

and in willDestroyElement:

document.removeEventListener("click", this.endDrag());

We have a few more event handlers in this component so this can get a bit repetitive.

This decorator allows us to do something like this:

@bind
endDrag() {
  this.set("clicked", true);
  console.log("Element clicked!");
}
// later
document.addEventListener("click", this.endDrag);
document.removeEventListener("click", this.endDrag);

Any objections to this?

[SamSaffron]

I am probably not the best person to review this perhaps @jjaffeux or @CvX can have a look (and at the entire change) ... overall I am super happy with all of this

[SamSaffron]

I say merge away, the odds of having problems are not enormous and we can catch them once it is deployed.