Now we have changed how hists stats are accounted especially when
filter(s) applied.  So add a test case to verify it.
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: http://lkml.kernel.org/r/1398396494-12811-2-git-send-email-namhyung@kernel.orgSigned-off-by: Jiri Olsa <jolsa@kernel.org>