fix(app): onThemeChange triggered twice

src/core/service/api/device/theme.js

@@ -7,6 +7,7 @@ import {
 } from '../../platform'
 
 const callbacks = []
+const oldCallbacks = []
 
 onMethod('onThemeChange', function (res) {
   callbacks.forEach(callbackId => {
@@ -20,12 +21,12 @@ export function onThemeChange (callbackId) {
 
 // 旧版本 API，后期文档更新后考虑移除
 onMethod('onUIStyleChange', function (res) {
-  callbacks.forEach(callbackId => {
+  oldCallbacks.forEach(callbackId => {
     invoke(callbackId, res)
   })
 })
 
 export function onUIStyleChange (callbackId) {
-  callbacks.push(callbackId)
+  oldCallbacks.push(callbackId)
   console.warn('The "uni.onUIStyleChange" API is deprecated, please use "uni.onThemeChange". Learn more: https://uniapp.dcloud.net.cn/api/system/theme.')
 }