[gtk+] Don't use one-stop gradients

[Emilio Pozuelo Monfort <epm src gnome org>]

commit b9f61e3a8e8040bd7719c4d85b6e623ee75420a3
Author: Emilio Pozuelo Monfort <pochu27 gmail com>
Date:   Thu Jul 28 17:12:25 2016 +0200

    Don't use one-stop gradients
    
    They are deprecated, which causes a warning that makes
    the test fail.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=769004

 .../linear-gradient-transition-to-other.css        |    4 ++--
 1 files changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/testsuite/reftests/linear-gradient-transition-to-other.css 
b/testsuite/reftests/linear-gradient-transition-to-other.css
index f8bbb86..65fdb8d 100644
--- a/testsuite/reftests/linear-gradient-transition-to-other.css
+++ b/testsuite/reftests/linear-gradient-transition-to-other.css
@@ -3,11 +3,11 @@
 }
 
 @keyframes ref {
-  100% { background-image: linear-gradient(to bottom, lime); }
+  100% { background-image: linear-gradient(to bottom, lime, lime); }
 }
 
 * {
-  background: linear-gradient(to bottom, red);
+  background: linear-gradient(to bottom, red, red);
   animation: anim steps(5,end) 20s;
 }