Fix windows build error (#14263)

* fix build

* take flash error message back and fix more windows lint error

* performance optimization

* own step to check lint for windows

Co-authored-by: 6543 <6543@obermui.de>

.drone.yml

@@ -33,6 +33,18 @@ steps:
       GOSUMDB: sum.golang.org
       TAGS: bindata sqlite sqlite_unlock_notify
 
+  - name: lint-backend-windows
+    pull: always
+    image: golang:1.15
+    commands:
+      - make golangci-lint vet
+    environment:
+      GOPROXY: https://goproxy.cn # proxy.golang.org is blocked in China, this proxy is not
+      GOSUMDB: sum.golang.org
+      TAGS: bindata sqlite sqlite_unlock_notify
+      GOOS: windows
+      GOARCH: amd64
+
   - name: lint-backend-gogit
     pull: always
     image: golang:1.15