Fix handling of last position for lazy deopt on X64, ARM and MIPS.

BUG=
R=jkummerow@chromium.org

Review URL: https://codereview.chromium.org/140773002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18642 ce2b1a6d-e550-0410-aec6-3dcde31c8c00
Enable allocation site pretenuring.

BUG=
R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/133703015

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@18643 ce2b1a6d-e550-0410-aec6-3dcde31c8c00