Editor Properties Panel: Unlink doesn't work for external links entered in IE

Using IE7 or IE8, enter the following text in the RTE:

http://example.com

Press enter, and the text is automatically changed into a link.

Click on it to get the property panel, and select 'Unlink'

As in CONF-19612, the link will still be regenerated when the page is saved.

Instead, it should be applying the 'nolink' macro.

This also applies to the 'unlink' item in the context menu.