Rework BuildCheckString() to be compatible with the other BuildCheck*() methods.

R=svenpanne@chromium.org

Review URL: https://codereview.chromium.org/79343009

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17985 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Pretenuring calculation fields in AllocationSite.

AllocationSite-based pretenuring needs additional fields to carry out
calculations.

R=hpayer@chromium.org

Review URL: https://codereview.chromium.org/43603002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@17986 ce2b1a6d-e550-0410-aec6-3dcde31c8c00