Bug 985980 - Restore off main thread logging for OS.File. r=froydnj

toolkit/components/osfile/modules/osfile_shared_allthreads.jsm

@@ -108,7 +108,7 @@ exports.defineLazyGetter = defineLazyGetter;
  * The choice of logger can be overridden with Config.TEST.
  */
 let gLogger;
-if (typeof console != "undefined" && console.log) {
+if (typeof window != "undefined" && window.console && console.log) {
   gLogger = console.log.bind(console, "OS");
 } else {
   gLogger = function(...args) {