fixup! vfs: forward the watchFile listener through RealFSProvider

Author: trivikr

test/parallel/test-vfs-real-provider-watch.js

@@ -44,8 +44,10 @@ assert.strictEqual(myVfs.provider.supportsWatch, true);
   // uv_fs_poll records the first stat asynchronously as the baseline and
   // only reports subsequent changes, so mutate the file only after that
   // baseline reflects 'a'; otherwise the change is folded into the baseline
-  // and the listener never fires.
-  setTimeout(() => fs.writeFileSync(path.join(root, 'wf.txt'), 'b'), 100);
+  // and the listener never fires. Change the size too, because some
+  // platforms (e.g. AIX) only report timestamps to the second, so a
+  // same-size rewrite within that second would look unchanged.
+  setTimeout(() => fs.writeFileSync(path.join(root, 'wf.txt'), 'bb'), 100);
   setTimeout(() => {
     myVfs.unwatchFile('/wf.txt', listener);
   }, 500);