Enable preaging of code objects when --optimize-for-size.
This change means that code which is never executed is garbage collected immediately, and code which is only executed once is collected more quickly (limiting heap growth), however, code which is re-executed is reset to the young age, thus being kept around for the same number of GC generations as currently.
BUG=280984
R=danno@chromium.org, hpayer@chromium.org
Review URL: https://codereview.chromium.org/
23480031
Patch from Ross McIlroy <rmcilroy@chromium.org>.
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@17343
ce2b1a6d-e550-0410-aec6-
3dcde31c8c00