Revert "Fix #1771 and probably others (#2286)" (#2299)

4f68984f2f

test-utils/domMock.js

@@ -87,13 +87,6 @@ module.exports = function(options) {
 		var index = this.childNodes.indexOf(child)
 		if (index > -1) {
 			this.childNodes.splice(index, 1)
-			// Yes, *this* is the behavior Chrome has and what FF is considering in
-			// https://bugzilla.mozilla.org/show_bug.cgi?id=559561
-			if (activeElement === child) {
-				var blur = $window.document.createEvent()
-				blur.initEvent("blur")
-				child.dispatchEvent(blur)
-			}
 			child.parentNode = null
 		}
 		else throw new TypeError("Failed to execute 'removeChild'")