Ticket #3788: accordion-animation.patch

Index: /Users/sgonzale/Documents/workspace/jQuery UI/ui/ui.accordion.js
===================================================================
--- /Users/sgonzale/Documents/workspace/jQuery UI/ui/ui.accordion.js	(revision 1844)
+++ /Users/sgonzale/Documents/workspace/jQuery UI/ui/ui.accordion.js	(working copy)
@@ -41,10 +41,7 @@
 		// wrap content elements in div against animation issues
 		this.headers
 			.next()
-				.wrap("
")
-				.addClass("ui-accordion-content")
-				.parent()
-					.addClass("ui-accordion-content-wrap ui-helper-reset ui-widget-content ui-corner-bottom");
+				.addClass("ui-accordion-content ui-helper-reset ui-widget-content ui-corner-bottom");
 
 		this.active = this._findActive(this.active || o.active).toggleClass("ui-state-default").toggleClass("ui-state-active").toggleClass("ui-corner-all").toggleClass("ui-corner-top");
 		this.active.parent().addClass('ui-accordion-selected');
@@ -403,17 +400,23 @@
 				return;
 			}
 			var hideHeight = options.toHide.height(),
-				showHeight = options.toShow.height(),
-				difference = showHeight / hideHeight,
-				overflow = options.toShow.css('overflow');
+				overflow = options.toShow.css('overflow'),
+				showProps = {},
+				hideProps = {},
+				fxAttrs = [ "height", "marginTop", "marginBottom", "paddingTop", "paddingBottom" ];
+			$.each(fxAttrs, function(i, prop) {
+				hideProps[prop] = 'hide';
+				showProps[prop] = parseFloat(options.toShow.css(prop));
+			});
 			options.toShow.css({ height: 0, overflow: 'hidden' }).show();
-			options.toHide.filter(":hidden").each(options.complete).end().filter(":visible").animate({height:"hide"},{
-				step: function(now) {
-					var current = (hideHeight - now) * difference;
+			options.toHide.filter(":hidden").each(options.complete).end().filter(":visible").animate(hideProps,{
+				step: function(now, settings) {
+					var percentDone = (settings.start - settings.now) / settings.start,
+						current = percentDone * showProps[settings.prop];
 					if ($.browser.msie || $.browser.opera) {
 						current = Math.ceil(current);
 					}
-					options.toShow.height( current );
+					options.toShow[0].style[settings.prop] = current + 'px';
 				},
 				duration: options.duration,
 				easing: options.easing,