generic/mutex: add default export

src/generic/locked_fs.ts

@@ -1,12 +1,12 @@
-import {Mutex} from './mutex';
+import Mutex from './mutex';
 import {FileSystem, SynchronousFileSystem} from '../core/file_system';
 import {ApiError, ErrorCode} from '../core/api_error';
 import {FileFlag, ActionType} from '../core/file_flag';
 import {default as Stats, FileType} from '../core/node_fs_stats';
 import {File} from '../core/file';
 
 // TODO: also implement LockedFile to ensure that operations on files
-// also grab the appropriate locks.
+// also grab the appropriate locks?.
 /*
 export LockedFile<T extends File> implements File {
   private _file: File;

src/generic/mutex.ts

@@ -2,7 +2,7 @@
 declare var setImmediate: (cb: Function) => void;
 
 /// non-recursive mutex
-export class Mutex {
+export default class Mutex {
   private _locked: boolean = false;
   private _waiters: Function[] = [];