fix forgot removed records when deleting user (#5429)

* fix forgot removed records when deleting user

* fix migration

* fix rewritekey lock on sqlite

* remove unused codes

models/migrations/v75.go

@@ -0,0 +1,33 @@
+// Copyright 2018 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/builder"
+	"github.com/go-xorm/xorm"
+)
+
+func clearNonusedData(x *xorm.Engine) error {
+	condDelete := func(colName string) builder.Cond {
+		return builder.NotIn(colName, builder.Select("id").From("user"))
+	}
+
+	if _, err := x.Exec(builder.Delete(condDelete("uid")).From("team_user")); err != nil {
+		return err
+	}
+
+	if _, err := x.Exec(builder.Delete(condDelete("user_id")).From("collaboration")); err != nil {
+		return err
+	}
+
+	if _, err := x.Exec(builder.Delete(condDelete("user_id")).From("stop_watch")); err != nil {
+		return err
+	}
+
+	if _, err := x.Exec(builder.Delete(condDelete("owner_id")).From("gpg_key")); err != nil {
+		return err
+	}
+	return nil
+}