[metacity] libmetacity: correctly center button vertically

[Alberts Muktupāvels <muktupavels src gnome org>]

commit c6b586dc2906a2d5e8ed1962ba5a654921670395
Author: Alberts Muktupāvels <alberts muktupavels gmail com>
Date:   Sun Feb 7 22:03:26 2016 +0200

    libmetacity: correctly center button vertically

 libmetacity/meta-theme-gtk.c |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/libmetacity/meta-theme-gtk.c b/libmetacity/meta-theme-gtk.c
index e1b9ee5..8546335 100644
--- a/libmetacity/meta-theme-gtk.c
+++ b/libmetacity/meta-theme-gtk.c
@@ -557,7 +557,7 @@ meta_theme_gtk_calc_geometry (MetaThemeImpl          *impl,
   content_width = width -
                   (fgeom->content_border.left + borders.invisible.left) -
                   (fgeom->content_border.right + borders.invisible.right);
-  content_height = borders.visible.top - fgeom->content_border.top - fgeom->content_border.bottom;
+  content_height = borders.visible.top - layout->gtk.frame_border.top;
 
   button_width = MAX ((gint) layout->gtk.icon_size, layout->gtk.button_min_size.width) +
                  layout->button_border.left + layout->button_border.right;
@@ -695,7 +695,7 @@ meta_theme_gtk_calc_geometry (MetaThemeImpl          *impl,
 
   /* center buttons vertically */
   button_y = fgeom->content_border.top + borders.invisible.top +
-             MAX(content_height - button_height, 0) / 2;
+             (content_height - button_height) / 2;
 
   /* right edge of farthest-right button */
   x = width - fgeom->content_border.right - borders.invisible.right;