Fixing potentially problematic usage of OS::StrDup that caused some strings to be allocated with malloc() but freed with delete[].
Review URL: http://codereview.chromium.org/48126

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@1531 ce2b1a6d-e550-0410-aec6-3dcde31c8c00