Merge 102392 - Line breaks are lost when pasted into textarea text starting with a blank line set while textarea is hidden
Reviewed by Tony Chang.
The bug was caused by the code that generated text out of pre-rendered text was generating div's inside the fragment
pasted into textarea even though serialization algorithm in textarea doesn't handle block elements.
Fixed the bug by special-casing this in createFragmentFromText. In the long run, we should really get rid of this
whole pre-rendering trick.