All: Drop support for jQueries different than the latest for each major

Also, remove the ability to run the test suite in jQuery <1.12.4 & <2.2.4.

Closes gh-2249

1 files changed, 0 insertions, 9 deletions

diff --git a/ui/effect.js b/ui/effect.js
index 2232e041d..ac9b0c809 100644
--- a/ui/effect.js
+++ b/ui/effect.js
@@ -125,15 +125,6 @@ function styleDifference( oldStyle, newStyle ) {
 	return diff;
 }
 
-// Support: jQuery <1.8
-if ( !$.fn.addBack ) {
-	$.fn.addBack = function( selector ) {
-		return this.add( selector == null ?
-			this.prevObject : this.prevObject.filter( selector )
-		);
-	};
-}
-
 $.effects.animateClass = function( value, duration, easing, callback ) {
 	var o = $.speed( duration, easing, callback );