[gitg/fix-deprecation-set_background] Fix deprecation set_background

[Alberto Fanjul <albfan src gnome org>]

commit d8ba28be7641ac4999ab0a3e95d5d27d178c94c8
Author: Gaurav Agrawal <agrawalgaurav1999 gmail com>
Date:   Tue Mar 26 13:25:55 2019 +0530

    Fix deprecation set_background

 libgitg/gitg-progress-bin.vala | 2 --
 1 file changed, 2 deletions(-)
---
diff --git a/libgitg/gitg-progress-bin.vala b/libgitg/gitg-progress-bin.vala
index 61ef0430..96a14512 100644
--- a/libgitg/gitg-progress-bin.vala
+++ b/libgitg/gitg-progress-bin.vala
@@ -62,8 +62,6 @@ namespace Gitg
                        var window = new Gdk.Window(get_parent_window(),
                                                    attributes, attributes_mask);
 
-                       var context = get_style_context();
-                       context.set_background(window);
 
                        set_window(window);
                        window.set_user_data(this);