[fix][32750] IE 10 - Isis -> Image can't be inserted via Image Button. Fixes #3932

http://joomlacode.org/gf/project/joomla/tracker/?action=TrackerItemEdit&tracker_item_id=32750&start=0

1. Use Internet Explorer 10
2. edit or write an article
3. Click on Image button below
4. choose an image and click on insert.
5. Nothing happens.
6. apply patch
7. clean cache
8. redo 1-4 and make sure it work now.