perf gtk/browser: Trim column header string when event group enabled

When event group feature is enabled, each column header is expanded to
match with the whole group column width.  But this is not needed for
GTK+ browser since ti usually use variable-width fonts.  So trim it.

Signed-off-by: Namhyung Kim <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Jiri Olsa <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Pekka Enberg <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Stephane Eranian <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Arnaldo Carvalho de Melo <[email protected]>

tools/perf/ui/gtk/hists.c

@@ -170,7 +170,7 @@ static void perf_gtk__show_hists(GtkWidget *window, struct hists *hists)
 		fmt->header(&hpp);
 
 		gtk_tree_view_insert_column_with_attributes(GTK_TREE_VIEW(view),
-							    -1, s,
+							    -1, ltrim(s),
 							    renderer, "markup",
 							    col_idx++, NULL);
 	}