Media projections require a foreground service of type ServiceInfo.FOREGROUND_SERVICE_TYPE_MEDIA_PRO
Android Q (Android10) 中，MediaProjection必须在前台服务中进行
参考链接：https://blog.csdn.net/qq_36332133/article/details/96485285
关键是要声明权限
<uses-permission android:name="android.permission.FOREGROUND_SERVICE" />
然后以
startForegroundService(service);的方式启动服务
同时不要忘记startForeground(id, notification);设置服务，
不然会报异常
Context.startForegroundService() did not then call Service.startForeground()
