Partially revert "Unflake and speedup JsNative*Sample cpu profile tests"

This reverts the test expectations of commit r22345. Several cpu profiler flakes were happening lately.

BUG=v8:2999
LOG=n
R=bmeurer@chromium.org
TBR=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/418843002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@22588 ce2b1a6d-e550-0410-aec6-3dcde31c8c00