The implementation of this method is required to be able to reflect correctly the state of the B, I and U buttons in the inspector bar also when the selection is a caret selection.
<rdar://problem/9325158>
Created attachment 123826 [details] patch
After discussing this further with Darin, we've decided to implement typingAttributes in WebView. I've changed the title of the bug to reflect this.
Created attachment 123979 [details] patch2
http://trac.webkit.org/changeset/105908
This caused bug 77432.