Accordion: Start the accordion animation before changing classes. Fixes #6720 - Accordion: ol numbering bug.

Thanks Tony Ross.

Author: scottgonzalez

ui/jquery.ui.accordion.js

@@ -338,8 +338,26 @@ $.widget( "ui.accordion", {
 			return;
 		}
 
+		// find elements to show and hide
+		var active = this.active,
+			toShow = clicked.next(),
+			toHide = this.active.next(),
+			data = {
+				options: options,
+				newHeader: clickedIsActive && options.collapsible ? $([]) : clicked,
+				oldHeader: this.active,
+				newContent: clickedIsActive && options.collapsible ? $([]) : toShow,
+				oldContent: toHide
+			},
+			down = this.headers.index( this.active[0] ) > this.headers.index( clicked[0] );
+
+		// when the call to ._toggle() comes after the class changes
+		// it causes a very odd bug in IE 8 (see #6720)
+		this.active = clickedIsActive ? $([]) : clicked;
+		this._toggle( toShow, toHide, data, clickedIsActive, down );
+
 		// switch classes
-		this.active
+		active
 			.removeClass( "ui-state-active ui-corner-top" )
 			.addClass( "ui-state-default ui-corner-all" )
 			.children( ".ui-icon" )
@@ -357,21 +375,6 @@ $.widget( "ui.accordion", {
 				.addClass( "ui-accordion-content-active" );
 		}
 
-		// find elements to show and hide
-		var toShow = clicked.next(),
-			toHide = this.active.next(),
-			data = {
-				options: options,
-				newHeader: clickedIsActive && options.collapsible ? $([]) : clicked,
-				oldHeader: this.active,
-				newContent: clickedIsActive && options.collapsible ? $([]) : toShow,
-				oldContent: toHide
-			},
-			down = this.headers.index( this.active[0] ) > this.headers.index( clicked[0] );
-
-		this.active = clickedIsActive ? $([]) : clicked;
-		this._toggle( toShow, toHide, data, clickedIsActive, down );
-
 		return;
 	},