all: Add filesystem notification support

GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/3986

vendor/github.com/zillode/notify/watcher_stub.go

@@ -0,0 +1,23 @@
+// Copyright (c) 2014-2015 The Notify Authors. All rights reserved.
+// Use of this source code is governed by the MIT license that can be
+// found in the LICENSE file.
+
+// +build !darwin,!linux,!freebsd,!dragonfly,!netbsd,!openbsd,!windows
+// +build !kqueue,!solaris
+
+package notify
+
+import "errors"
+
+type stub struct{ error }
+
+// newWatcher stub.
+func newWatcher(chan<- EventInfo) watcher {
+	return stub{errors.New("notify: not implemented")}
+}
+
+// Following methods implement notify.watcher interface.
+func (s stub) Watch(string, Event) error          { return s }
+func (s stub) Rewatch(string, Event, Event) error { return s }
+func (s stub) Unwatch(string) (err error)         { return s }
+func (s stub) Close() error                       { return s }