tooltip.js: getBoundingClientRect method existence check is unnecessary?

Created by: cvrebert

Element.getBoundingClientRect() seems extremely well-supported: https://developer.mozilla.org/en-US/docs/Web/API/Element.getBoundingClientRect#Browser_compatibility So then, is there a reason that there's a check in tooltip.js for whether this method exists?: https://github.com/twbs/bootstrap/blob/f9ffb4993215687bb241cab1151956e6df1922cd/js/tooltip.js#L324

To: @fat X-Ref: #14090