https://developer.android.google.cn/index.html
https://source.android.google.cn/devices/architecture/treble
http://www.jb51.net/article/109857.htm
http://blog.csdn.net/zhenjie_chang/article/details/52513388
https://blog.csdn.net/Gaugamela/article/details/52981984
PowerManagerService中也有Doze模式，和此处的Doze模式不一样，其实此处叫Device Idle模式更容易区分