[gtk+] Adwaita: parametric headerbar_fill highlight

[Lapo Calamandrei <lapo src gnome org>]

commit c1e831e595154f5fb42d5848317d3575bd334296
Author: Lapo Calamandrei <calamandrei gmail com>
Date:   Tue Sep 2 20:39:25 2014 +0200

    Adwaita: parametric headerbar_fill highlight

 gtk/resources/theme/Adwaita/_drawing.scss |   10 ++++++++--
 1 files changed, 8 insertions(+), 2 deletions(-)
---
diff --git a/gtk/resources/theme/Adwaita/_drawing.scss b/gtk/resources/theme/Adwaita/_drawing.scss
index 3c309f3..bb86909 100644
--- a/gtk/resources/theme/Adwaita/_drawing.scss
+++ b/gtk/resources/theme/Adwaita/_drawing.scss
@@ -413,9 +413,15 @@
   @return linear-gradient(to bottom, lighten($c,4%), $c);
 }
 
- mixin headerbar_fill($c:$bg_color) {
+ mixin headerbar_fill($c:$bg_color, $hc:$top_hilight) {
+  //
+  // headerbar fill
+  //
+  // $c:  base color
+  // $hc: top highlight color
+  // 
   background-image: headerbar_gradient($c);
   box-shadow: inset 0 -1px mix($borders_color, $c, 30%), // bottom shade
-              inset 0 1px $top_hilight; // top highlight
+              inset 0 1px $hc; // top highlight
 
 }