Commented Unassigned: TabControl not working on IE8 [27748]

Hi there any chance you could fix the IE8 Tab Control problem in ajax control toolkit?

I have tracked down the problem to the following line (not doing the same thing in IE8 and IE11).

Line 199 (jQuery.jQueryUIWidget.debug.js)
```
this.options = $.widget.extend({},
this.options,
this._getCreateOptions(),
options);
```

In IE8 the methods defined in the prototype aren't copied while on IE11 they are.

So when IE8 tries to access "opt.owner.get_tabs().length;" we get a "Object doesn't support this property or method" error.

Comments: Ignore my comment above the error seems to be in jquery's isPlainObject method, but replacing it with the latest version dosent resolve the error. The problem is that options.owner is not copied correctly on IE8, and looses its get_tabs method. As a last resort i modified $.widget.extend by changing ``` if ($.isPlainObject(value)) { ``` to ``` if ($.isPlainObject(value) && key != "owner") { ``` Also jQueries own extend method seems to have the same problem when you do a deep copy. Inside isPlainObject the following function returns different results. !core_hasOwn.call(obj.constructor.prototype, "isPrototypeOf") IE11 True IE8 False