Undo changes since gsoc in media_confirm_delete

Since the Gsoc the use of decorators has simplified this function.
Reintroduce the same code as before Adidits blog branch made these
changes.

mediagoblin/user_pages/views.py

@@ -286,29 +286,11 @@ def media_collect(request, media):
 
 
 #TODO: Why does @user_may_delete_media not implicate @require_active_login?
-
+@get_media_entry_by_id
 @require_active_login
-def media_confirm_delete(request):
-    
-    allowed_state = [u'failed', u'processed']
-    media = None
-    for media_state in allowed_state:
-        media = request.db.MediaEntry.query.filter_by(id=request.matchdict['media_id'], state=media_state).first()
-        if media:
-            break
-    
-    if not media:
-        return render_404(request)
-    
-    given_username = request.matchdict.get('user')
-    if given_username and (given_username != media.get_uploader.username):
-        return render_404(request)
-    
-    uploader_id = media.uploader
-    if not (request.user.has_privilege(u'admin') or
-            request.user.id == uploader_id):
-        raise Forbidden()
-    
+@user_may_delete_media
+def media_confirm_delete(request, media):
+
     form = user_forms.ConfirmDeleteForm(request.form)
 
     if request.method == 'POST' and form.validate():