perf ui/gtk: Setup browser window early

The ui__error/warning functions use gtk infobar or statusbar and
pr_* functions use statusbar too.  But after perf gtk context
created but those infobar and/or statusbar not yet set up,
calling one of those functions will get a segment fault.

Although current code has no problem, move these setting as early
as possible so that it can prevent the segfault from future change.

Cc: Pekka Enberg <penberg@kernel.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
1 file changed