Saving Hydrogen code stubs in the snapshot requires us to respect the availability of VFP32DREGS.

BUG=

Review URL: https://codereview.chromium.org/13878011

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@14338 ce2b1a6d-e550-0410-aec6-3dcde31c8c00