fix: App平台首次安装弹权限框时报错的Bug

src/core/service/bridge/on.js

@@ -54,6 +54,9 @@ export default function initOn (on, {
 
   function onAppEnterForeground () {
     const pages = getCurrentPages()
+    if (pages.length === 0) {
+      return
+    }
     const page = pages[pages.length - 1]
     const args = {
       path: page.route,