Fixes #4251.  For FF, Textarea postCreate now checks that the iframe is fully initialized, and if not, allows the iframe to run postCreate when its ready.
Fixes #4251.  For FF, Textarea postCreate now checks that the iframe is fully initialized,
and if not, allows the iframe to run postCreate when its ready.

git-svn-id: 674a2d6b1e32e53f607eb824547723f32280967e@10430 560b804f-0ae3-0310-86f3-f6aa0a117693

redaktor/deliteful