Why in Chrome it's $("html") and in Safari $("body") works for the scroll effect? How could I make a perfect solution?

Question

I found this is exactly what I want: jQuery .scrollTop(); + animation

var body = $("html, body");
body.stop().animate({scrollTop:0}, 500, 'swing', function() { 
  alert("Finished animating");
});

But the problem as a comment mentioned in the question is that the trigger function would fire twice.

I realize that it's because $("html, body") get two elements binding this event.

However, I noticed that I can't just simply remove one because in Safari it's body that works while in Chrome it's html that works.

And I don't know what would happen on other devices that I could access.

So, is there any perfect solution for this that I don't need to fire twice the function?