Enabling splitting building with snapshots in to building the mksnapshot executable and building with a snapshot to facilitate building for ARM with a crosstool compiler.
Review URL: http://codereview.chromium.org/19014

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1188 ce2b1a6d-e550-0410-aec6-3dcde31c8c00