Accordion: Use .css() to clear the height, instead of .height().

(cherry picked from commit 2553d61)

Author: scottgonzalez

ui/jquery.ui.accordion.js

@@ -325,7 +325,7 @@ $.widget( "ui.accordion", {
 			maxHeight = 0;
 			this.headers.next()
 				.each(function() {
-					maxHeight = Math.max( maxHeight, $( this ).height( "" ).height() );
+					maxHeight = Math.max( maxHeight, $( this ).css( "height", "" ).height() );
 				})
 				.height( maxHeight );
 		}