[gnome-shell-extensions] user-theme: Temporarily work around a gnome-shell regression

[Florian Müllner <fmuellner src gnome org>]

commit dd3c7ca199d8675f454ba4ab12a8adc32ecd0ed9
Author: Florian Müllner <fmuellner gnome org>
Date:   Thu Nov 27 14:32:28 2014 +0000

    user-theme: Temporarily work around a gnome-shell regression
    
    setThemeStylesheet() stopped accepting %null to revert to the default
    stylesheet. The issue is fixed in gnome-shell master, but work around
    it for 3.15.2 to not ship broken (again).

 extensions/user-theme/extension.js |   10 ++++++----
 1 files changed, 6 insertions(+), 4 deletions(-)
---
diff --git a/extensions/user-theme/extension.js b/extensions/user-theme/extension.js
index b36d36a..b9dc30e 100644
--- a/extensions/user-theme/extension.js
+++ b/extensions/user-theme/extension.js
@@ -30,7 +30,7 @@ const ThemeManager = new Lang.Class({
             this._changedId = 0;
         }
 
-        Main.setThemeStylesheet(null);
+        Main._cssStylesheet = null;
         Main.loadTheme();
     },
 
@@ -57,11 +57,13 @@ const ThemeManager = new Lang.Class({
             }
         }
 
-        if (_stylesheet)
+        if (_stylesheet) {
             global.log('loading user theme: ' + _stylesheet);
-        else
+            Main.setThemeStylesheet(_stylesheet);
+        } else {
             global.log('loading default theme (Adwaita)');
-        Main.setThemeStylesheet(_stylesheet);
+            Main._cssStylesheet = null;
+        }
         Main.loadTheme();
     }
 });