[gnome-shell-extensions] user-theme: fix resetting theme to null

[Giovanni Campagna <gcampagna src gnome org>]

commit d942e255f734eddc4bb1d4698aea75aafe52072f
Author: Giovanni Campagna <gcampagna src gnome org>
Date:   Mon May 2 18:07:39 2011 +0200

    user-theme: fix resetting theme to null
    
    Previously null stylesheets were ignored, making it impossible to
    reset the default. We still need to filter out invalid (non existing)
    stylesheets, as no check is performed by shell code.

 extensions/user-theme/extension.js |   13 ++++++++-----
 1 files changed, 8 insertions(+), 5 deletions(-)
---
diff --git a/extensions/user-theme/extension.js b/extensions/user-theme/extension.js
index a9f095e..b0b041e 100644
--- a/extensions/user-theme/extension.js
+++ b/extensions/user-theme/extension.js
@@ -29,13 +29,16 @@ ThemeManager.prototype = {
             file = Gio.file_new_for_path(_userCssStylesheet);
             if (file.query_exists(null))
                 _stylesheet = _userCssStylesheet;
+            else
+                _stylesheet = null;
         }
 
-        if (_stylesheet) {
-            global.log('loading user theme: ' + _stylesheet)
-            Main.setThemeStylesheet(_stylesheet);
-            Main.loadTheme();
-        }
+        if (_stylesheet)
+            global.log('loading user theme: ' + _stylesheet);
+        else
+            global.log('loading default theme (Adwaita)');
+        Main.setThemeStylesheet(_stylesheet);
+        Main.loadTheme();
     }
 }