In some cases the assert that the test function is not optimized fails
because the function may be optimized already after the second invocation.
(e.g. when running slow in debug mode)
Review URL: http://codereview.chromium.org/7778009

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@9034 ce2b1a6d-e550-0410-aec6-3dcde31c8c00