It doesn't really belong in CallFrame to begin with.
<rdar://problem/43655753>
Created attachment 347955 [details] proposed patch.
Created attachment 347958 [details] proposed patch w/ GTK build fix.
Comment on attachment 347958 [details] proposed patch w/ GTK build fix. r=me
Thanks for the review. Landed in r235254: <http://trac.webkit.org/r235254>.