Enable compiled transitions by default.

R=mvstanton@chromium.org

Review URL: https://codereview.chromium.org/19005005

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@15630 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Remove filler map when folding allocations and turn on allocation folding.

BUG=
R=titzer@chromium.org

Review URL: https://codereview.chromium.org/18384004

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@15631 ce2b1a6d-e550-0410-aec6-3dcde31c8c00