vendor: github.com/Zillode/notify is now github.com/syncthing/notify (#4813)

Given that we've taken on the resposibility of maintaining this forked
package I've added it to the Syncthing organization. We still vendor it
like an external package, because it's convenient to keep it as a fork
of upstream to easier merge and file pull requests towards them.

vendor/github.com/syncthing/notify/watchpoint_readdcw.go

@@ -0,0 +1,38 @@
+// 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 windows
+
+package notify
+
+// eventmask uses ei to create a new event which contains internal flags used by
+// notify package logic. If one of FileAction* masks is detected, this function
+// adds corresponding FileNotifyChange* values. This allows non registered
+// FileAction* events to be passed on.
+func eventmask(ei EventInfo, extra Event) (e Event) {
+	if e = ei.Event() | extra; e&fileActionAll != 0 {
+		if ev, ok := ei.(*event); ok {
+			switch ev.ftype {
+			case fTypeFile:
+				e |= FileNotifyChangeFileName
+			case fTypeDirectory:
+				e |= FileNotifyChangeDirName
+			case fTypeUnknown:
+				e |= fileNotifyChangeModified
+			}
+			return e &^ fileActionAll
+		}
+	}
+	return
+}
+
+// matches reports a match only when:
+//
+//   - for user events, when event is present in the given set
+//   - for internal events, when additionally both event and set have omit bit set
+//
+// Internal events must not be sent to user channels and vice versa.
+func matches(set, event Event) bool {
+	return (set&omit)^(event&omit) == 0 && (set&event == event || set&fileNotifyChangeModified&event != 0)
+}