const {interfaces: Ci, utils: Cu, manager: Cm} = Components;
Cu.import("resource://gre/modules/Services.jsm");
let cmanifest = Services.dirsvc.get("UChrm", Ci.nsIFile);
cmanifest.append("chrome.manifest");
Cm.QueryInterface(Ci.nsIComponentRegistrar).autoRegister(cmanifest);