Because of varying floating-point precision, the slow case is hard to
test with explicit values. Instead, we check that sine and cosine do
not return the same value (the regression was that the slow case of
cosine accidentally did sine instead of cosine).
Review URL: http://codereview.chromium.org/126123
git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2169 ce2b1a6d-e550-0410-aec6-3dcde31c8c00