set incognito mode for public.php calls. Because in this case ownCloud should...

set incognito mode for public.php calls. Because in this case ownCloud should always work the same way as if no user is logged in

public.php

@@ -20,6 +20,7 @@ try {
 
 	OC_Util::checkAppEnabled($app);
 	OC_App::loadApp($app);
+	OC_User::setIncognitoMode(true);
 
 	require_once OC_App::getAppPath($app) .'/'. $parts[1];