BUG=51594
TEST=test-cpu-profiler/CrashIfStoppingLastNonExistentProfile

Review URL: http://codereview.chromium.org/3108004

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@5230 ce2b1a6d-e550-0410-aec6-3dcde31c8c00