If the instanceof stub was requested to deliver true/false objects as the result instead of 0/1 then 0/1 was actually returned if the builtin INSTANCE_OF ended up being called. This is now fixed.

BUG=v8:1020
TEST=test/mjsunit/regress/regress-1020.js
Review URL: http://codereview.chromium.org/6014013

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@6185 ce2b1a6d-e550-0410-aec6-3dcde31c8c00