fs: replace a bind() with a top-level function

#11225 introduce an unnecessary
bind() when closing a stream. This PR replaces that bind() with a
top-level function.

PR-URL: #13474
Reviewed-By: Refael Ackermann <refack@gmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Brian White <mscdex@mscdex.net>
Reviewed-By: Evan Lucas <evanlucas@me.com>

lib/fs.js

@@ -2016,7 +2016,7 @@ ReadStream.prototype.close = function(cb) {
 
   if (this.closed || typeof this.fd !== 'number') {
     if (typeof this.fd !== 'number') {
-      this.once('open', this.close.bind(this, null));
+      this.once('open', closeOnOpen);
       return;
     }
     return process.nextTick(() => this.emit('close'));
@@ -2034,6 +2034,11 @@ ReadStream.prototype.close = function(cb) {
   this.fd = null;
 };
 
+// needed because as it will be called with arguments
+// that does not match this.close() signature
+function closeOnOpen(fd) {
+  this.close();
+}
 
 fs.createWriteStream = function(path, options) {
   return new WriteStream(path, options);