Fixing all together.
Created attachment 306109 [details] async call frames - before (LTR)
Created attachment 306110 [details] async call frames - before (RTL)
Created attachment 306111 [details] async call frames - after (RTL)
Created attachment 306113 [details] Proposed Fix
Created attachment 306114 [details] Proposed Fix
Comment on attachment 306114 [details] Proposed Fix r=me
Comment on attachment 306114 [details] Proposed Fix Clearing flags on attachment: 306114 Committed r214846: <http://trac.webkit.org/changeset/214846>
All reviewed patches have been landed. Closing bug.