check animations all stop bug.

src/Animations/babylon.animatable.ts

@@ -119,7 +119,7 @@
                         numberOfAnimationsStopped++;
                     }
 
-                    if (animations.length == numberOfAnimationsStopped) {
+                    if (animations.length == 0) {
                         this._scene._activeAnimatables.splice(idx, 1);
 
                         if (this.onAnimationEnd) {
@@ -191,4 +191,4 @@
             return running;
         }
     }
-} 
+}