JSC::WeakImpl already asserts that the weak pointee is a non-null JSCell*. We should enforce this at compile time with narrower types.
Created attachment 260760 [details] Patch
Comment on attachment 260760 [details] Patch r=me
Comment on attachment 260760 [details] Patch Clearing flags on attachment: 260760 Committed r189616: <http://trac.webkit.org/changeset/189616>
All reviewed patches have been landed. Closing bug.
Re-opened since this is blocked by bug 149456