[gtk+] Adwaita: remove the image effect for buttons icons in backdrop

[Lapo Calamandrei <lapo src gnome org>]

commit 71f328e8c230c54cac8b450a05a302389461d1a5
Author: Lapo Calamandrei <calamandrei gmail com>
Date:   Tue Jul 8 16:42:10 2014 +0200

    Adwaita: remove the image effect for buttons icons in backdrop

 gtk/resources/theme/Adwaita/_common.scss           |    1 +
 gtk/resources/theme/Adwaita/gtk-contained-dark.css |    3 ++-
 gtk/resources/theme/Adwaita/gtk-contained.css      |    3 ++-
 3 files changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/gtk/resources/theme/Adwaita/_common.scss b/gtk/resources/theme/Adwaita/_common.scss
index 042967d..a189ce2 100644
--- a/gtk/resources/theme/Adwaita/_common.scss
+++ b/gtk/resources/theme/Adwaita/_common.scss
@@ -254,6 +254,7 @@ GtkLabel {
   }
   &:backdrop, &.flat:backdrop {
     @include button(backdrop);
+    -gtk-image-effect: none;
     &:active {
       @include button(backdrop-active);
     }
diff --git a/gtk/resources/theme/Adwaita/gtk-contained-dark.css 
b/gtk/resources/theme/Adwaita/gtk-contained-dark.css
index bb18f04..f66fb0c 100644
--- a/gtk/resources/theme/Adwaita/gtk-contained-dark.css
+++ b/gtk/resources/theme/Adwaita/gtk-contained-dark.css
@@ -283,7 +283,8 @@
     background-image: linear-gradient(to bottom, #393f3f);
     text-shadow: none;
     icon-shadow: none;
-    box-shadow: inset 0 1px rgba(255, 255, 255, 0), 0 1px rgba(255, 255, 255, 0); }
+    box-shadow: inset 0 1px rgba(255, 255, 255, 0), 0 1px rgba(255, 255, 255, 0);
+    -gtk-image-effect: none; }
     .button:backdrop:active, .button.flat:backdrop:active {
       border-style: solid;
       color: #c9cbc9;
diff --git a/gtk/resources/theme/Adwaita/gtk-contained.css b/gtk/resources/theme/Adwaita/gtk-contained.css
index 4647b92..0b8042c 100644
--- a/gtk/resources/theme/Adwaita/gtk-contained.css
+++ b/gtk/resources/theme/Adwaita/gtk-contained.css
@@ -275,7 +275,8 @@
     background-image: linear-gradient(to bottom, #ededed);
     text-shadow: none;
     icon-shadow: none;
-    box-shadow: inset 0 1px rgba(255, 255, 255, 0), 0 1px rgba(255, 255, 255, 0); }
+    box-shadow: inset 0 1px rgba(255, 255, 255, 0), 0 1px rgba(255, 255, 255, 0);
+    -gtk-image-effect: none; }
     .button:backdrop:active, .button.flat:backdrop:active {
       border-style: solid;
       color: #54595a;