Move sql store code into store/sqlstore package (#7502)

* move sql store code into store/sqlstore package

* move non-sql constants back up to store

* fix api test

* derp

store/sqlstore/upgrade_test.go

@@ -0,0 +1,41 @@
+// Copyright (c) 2017-present Mattermost, Inc. All Rights Reserved.
+// See License.txt for license information.
+
+package sqlstore
+
+import (
+	"testing"
+
+	"github.com/mattermost/mattermost-server/model"
+	"github.com/mattermost/mattermost-server/store"
+)
+
+func TestStoreUpgrade(t *testing.T) {
+	ss := Setup()
+
+	saveSchemaVersion(ss.(*store.LayeredStore).DatabaseLayer.(SqlStore), VERSION_3_0_0)
+	UpgradeDatabase(ss.(*store.LayeredStore).DatabaseLayer.(SqlStore))
+
+	saveSchemaVersion(ss.(*store.LayeredStore).DatabaseLayer.(SqlStore), "")
+	UpgradeDatabase(ss.(*store.LayeredStore).DatabaseLayer.(SqlStore))
+}
+
+func TestSaveSchemaVersion(t *testing.T) {
+	ss := Setup()
+
+	saveSchemaVersion(ss.(*store.LayeredStore).DatabaseLayer.(SqlStore), VERSION_3_0_0)
+	if result := <-ss.System().Get(); result.Err != nil {
+		t.Fatal(result.Err)
+	} else {
+		props := result.Data.(model.StringMap)
+		if props["Version"] != VERSION_3_0_0 {
+			t.Fatal("version not updated")
+		}
+	}
+
+	if ss.(*store.LayeredStore).DatabaseLayer.(SqlStore).GetCurrentSchemaVersion() != VERSION_3_0_0 {
+		t.Fatal("version not updated")
+	}
+
+	saveSchemaVersion(ss.(*store.LayeredStore).DatabaseLayer.(SqlStore), model.CurrentVersion)
+}