dropEventTimerSubscription: late unsubscription

[LeoNiedermeier]

Related to #224

The dropEventTimerSubscription is not unsubscribed after dropped finished. It is still there and fires until the next drop event or the component is destroyed. This has the side effect that the angular change detection also runs every 200ms.

Maybe with a code like the following insteded of just using numOfActiveReadEntries--, the dropEventTimer in

ngx-file-drop/src/ngx-file-drop/ngx-file-drop.component.ts

Line 225 in b63662c

this.dropEventTimerSubscription = timer(200, 200)

is not necessary anymore:

  decrementNumOfActiveReadEntries () {
    this.numOfActiveReadEntries --;

    if (this.numOfActiveReadEntries == 0) {
      this.zone.run(() =>
       const files = this.files;
        this.files = [];
        this.onFileDrop.emit(files);
    }
  }

[elruss]

Is there a workaround for this? We use Angular's built-in testability object for QA, and the timer is preventing that object from stabilizing after a file drop.