Port r21093 (21e3836)

Original commit message:
Patching will
occur only when custom feedback needs to be gathered (future CLs).

Now rebased on https://codereview.chromium.org/254623002/, which moves the type feedback vector to the SharedFunctionInfo.

BUG=
R=plind44@gmail.com

Review URL: https://codereview.chromium.org/260753004

Patch from Balazs Kilvady <kilvadyb@homejinni.com>.

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@21105 ce2b1a6d-e550-0410-aec6-3dcde31c8c00