Fix orgnization user watch repository (#2670)

* remove orgnization watch repositories

* fix migration

* fix typo and missing change

* remove unused code

models/migrations/v46.go

@@ -0,0 +1,36 @@
+// Copyright 2017 The Gitea Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package migrations
+
+import (
+	"github.com/go-xorm/xorm"
+)
+
+func removeOrganizationWatchRepo(x *xorm.Engine) error {
+	// UserType defines the user type
+	type UserType int
+
+	const (
+		// UserTypeIndividual defines an individual user
+		UserTypeIndividual UserType = iota // Historic reason to make it starts at 0.
+
+		// UserTypeOrganization defines an organization
+		UserTypeOrganization
+	)
+
+	sess := x.NewSession()
+	defer sess.Close()
+	if err := sess.Begin(); err != nil {
+		return err
+	}
+	if _, err := sess.Exec("DELETE FROM watch WHERE id IN (SELECT watch.id FROM watch INNER JOIN user ON watch.user_id = user.id WHERE `user`.`type` = ?)", UserTypeOrganization); err != nil {
+		return err
+	}
+	if _, err := sess.Exec("UPDATE `repository` SET num_watches = (SELECT count(*) FROM watch WHERE `repository`.`id` = watch.repo_id)"); err != nil {
+		return err
+	}
+
+	return sess.Commit()
+}