[link] [IE] No link created in enter mode BR

[Garry Yao]

1. Load enterkey sample page, switch to enter mode BR;
2. Put cursor collapsed at any position;
3. Open Link dialog and fill in an URL, click OK.

• Actual: Text of the URL is inserted but not the link;

[Piotrek Koszuliński]

This is regression after ​http://dev.ckeditor.com/ticket/9474#comment:10

[Garry Yao]

Expired on master.