We don't test the no-GGC configuration and it's not clear why we have that. If we did have to disable generations, we could do it at run-time using one of the Options.
Created attachment 261761 [details] the patch
Comment on attachment 261761 [details] the patch r=me
Comment on attachment 261761 [details] the patch r=me too
Landed in http://trac.webkit.org/changeset/190129