Fix text format handling in TextField's replaceText
Fix text format handling in TextField's replaceText

Still bugs at least when adding text to the end in version 7

freedesktop-unofficial-mirror/swfdec__swfdec,freedesktop-unofficial-mirror/swfdec__swfdec,freedesktop-unofficial-mirror/swfdec__swfdec,mltframework/swfdec,mltframework/swfdec