When prepending a '-' to the function name, the function will not be optimized.

--hydrogen-filter=foo works as before.

--hydrogen-filter=-foo means don't optimize foo.
Review URL: https://chromiumcodereview.appspot.com/9691042

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@11036 ce2b1a6d-e550-0410-aec6-3dcde31c8c00