Remove requestAnimationFrame support. Fixes #9381.

src/effects.js

@@ -13,10 +13,7 @@ var elemdisplay = {},
 		// opacity animations
 		[ "opacity" ]
 	],
-	fxNow,
-	requestAnimationFrame = window.webkitRequestAnimationFrame ||
-		window.mozRequestAnimationFrame ||
-		window.oRequestAnimationFrame;
+	fxNow;
 
 jQuery.fn.extend({
 	show: function( speed, easing, callback ) {
@@ -392,8 +389,7 @@ jQuery.fx.prototype = {
 	// Start an animation from one number to another
 	custom: function( from, to, unit ) {
 		var self = this,
-			fx = jQuery.fx,
-			raf;
+			fx = jQuery.fx;
 
 		this.startTime = fxNow || createFxNow();
 		this.start = from;
@@ -409,20 +405,7 @@ jQuery.fx.prototype = {
 		t.elem = this.elem;
 
 		if ( t() && jQuery.timers.push(t) && !timerId ) {
-			// Use requestAnimationFrame instead of setInterval if available
-			if ( requestAnimationFrame ) {
-				timerId = true;
-				raf = function() {
-					// When timerId gets set to null at any point, this stops
-					if ( timerId ) {
-						requestAnimationFrame( raf );
-						fx.tick();
-					}
-				};
-				requestAnimationFrame( raf );
-			} else {
-				timerId = setInterval( fx.tick, fx.interval );
-			}
+			timerId = setInterval( fx.tick, fx.interval );
 		}
 	},