Tabs: fixed to work with empty nav list again.

Fixes #4997 - No longer possible to start with empty tab then add() elements dynamically.

tests/unit/tabs/tabs.html

@@ -42,6 +42,34 @@
 			<div id="colon:test"></div>
 			<div style="height: 300px;" id="inline-style"></div>
 		</div>
+		<div id="tabs3">
+			<div>
+				<ul id="tabs3-list">
+					<li><a href="#tabs3-1">1</a></li>
+				</ul>
+			</div>
+		</div>
+		<div id="tabs4">
+			<ul id="tabs4-list">
+				<li><a href="#tabs4-1">1</a></li>
+			</ul>
+			<ol>
+				<li><a href="#tabs4-1">1</a></li>
+			</ol>
+		</div>
+		<div id="tabs4a">
+			<ol id="tabs4a-list">
+				<li><a href="#tabs4a-1">1</a></li>
+			</ol>
+			<ul>
+				<li><a href="#tabs4a-1">1</a></li>
+			</ul>
+		</div>
+		<div id="tabs5">
+			<div>
+				<ul id="tabs5-list"></ul>
+			</div>
+		</div>
 	</div>
 </body>
 </html>

tests/unit/tabs/tabs_core.js

@@ -7,6 +7,24 @@ var el;
 
 module("tabs: core");
 
+test('navigation markup', function() {
+	el = $('#tabs3').tabs();
+	ok($('#tabs3-list').hasClass('ui-tabs-nav'), 'custom markup; allow list to be any descendant');
+	el.tabs('destroy');
+
+	el = $('#tabs4').tabs();
+	ok($('#tabs4-list').hasClass('ui-tabs-nav'), 'first list found becomes nav - ul');
+	el.tabs('destroy');
+
+	el = $('#tabs4a').tabs();
+	ok($('#tabs4a-list').hasClass('ui-tabs-nav'), 'first list found becomes nav - ol');
+	el.tabs('destroy');
+
+	el = $('#tabs5').tabs();
+	ok($('#tabs5-list').hasClass('ui-tabs-nav'), 'empty list can be used');
+	el.tabs('destroy');
+});
+
 test('ajax', function() {
 	expect(4);
 	stop();
@@ -34,6 +52,5 @@ test('ajax', function() {
 	});
 	
 });
-	
+
-	
 })(jQuery);

ui/jquery.ui.tabs.js

@@ -68,8 +68,7 @@ $.widget("ui.tabs", {
 
 	_tabify: function(init) {
 
-		// use $('li:first').parent() so we can find the first ul/ol in DOM order
+		this.list = this.element.find('ol,ul').eq(0);
-		this.list = this.element.find('li:first').parent();
 		this.lis = $('li:has(a[href])', this.list);
 		this.anchors = this.lis.map(function() { return $('a', this)[0]; });
 		this.panels = $([]);