perf hists: Introduce struct he_stat

The struct he_stat is for separating out statistics data of a hist
entry.  It is required for later changes.

It's just a mechanical change and should have no functional differences.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Cc: Arun Sharma <asharma@fb.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lkml.kernel.org/r/1349354994-17853-8-git-send-email-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

tools/perf/ui/gtk/browser.c

@@ -50,7 +50,7 @@ static int perf_gtk__hpp_color_ ## _name(struct perf_hpp *hpp,			\
 					 struct hist_entry *he)			\
 {										\
 	struct hists *hists = he->hists;					\
-	double percent = 100.0 * he->_field / hists->stats.total_period;	\
+	double percent = 100.0 * he->stat._field / hists->stats.total_period;	\
 	const char *markup;							\
 	int ret = 0;								\
 										\