NumberToString in runtime JavaScript is inlined through a call to a stub. Currently the stub only checks the number string cache and only if the number is a smi. Code is shared with the inlining of number string cache lookup when adding a smi to a string.
Review URL: http://codereview.chromium.org/604062

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@3865 ce2b1a6d-e550-0410-aec6-3dcde31c8c00