[gnome-shell] background: Don't prematurely remove file monitors

[Jasper St. Pierre <jstpierre src gnome org>]

commit 01f740ce69017f6305dd579c2eab55f0076ca6f6
Author: Jasper St. Pierre <jstpierre mecheye net>
Date:   Thu Dec 12 14:42:41 2013 -0500

    background: Don't prematurely remove file monitors
    
    We need to only remove file monitors when there's no other users
    of the content...

 js/ui/background.js |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/js/ui/background.js b/js/ui/background.js
index a56a0af..20a3a40 100644
--- a/js/ui/background.js
+++ b/js/ui/background.js
@@ -125,7 +125,8 @@ const BackgroundCache = new Lang.Class({
     removeImageContent: function(content) {
         let filename = content.get_filename();
 
-        if (filename && this._fileMonitors[filename])
+        let hasOtherUsers = this._images.some(function(content) { return filename == content.get_filename(); 
});
+        if (!hasOtherUsers)
             delete this._fileMonitors[filename];
 
         this._removeContent(this._images, content);