android 9 数据和wlan，以太网并存

1. 无连接网络不断开

android/frameworks/base/services/core/java/com/android/server/ConnectivityService.java

修改： teardownUnneededNetwork去掉nai.asyncChannel.disconnect();

2. 数据网络调整优先级最高

android/frameworks/opt/telephony/src/java/com/android/internal/telephony/dataconnection/DataConnection.java

修改：DcNetworkAgent优先级从50改为120

android/frameworks/opt/telephony/src/java/com/android/internal/telephony/dataconnection/TelephonyNetworkFactory.java

修改：TELEPHONY_NETWORK_SCORE从50改为80

3. 评分evalRequest默认启动网络，否则先打开数据后，wlan和以太网不会主动连接

android/frameworks/base/core/java/android/net/NetworkFactory.java

android/frameworks/opt/net/ethernet/java/com/android/server/ethernet/EthernetNetworkFactory.java

android/frameworks/opt/net/wifi/service/java/com/android/server/wifi/WifiStateMachine.java

修改：evalRequest方法

if(persistNetwork()){

log("persistNetwork:");

needNetworkFor(n.request, n.score);

}else

4. wlan和以太网连接后更新路由

android/frameworks/base/services/core/java/com/android/server/ConnectivityService.java

修改：updateLinkProperties，可在init.rc定义服务，使用setprop ctl.start启动

5. 更新路由可修改ip源码，参考ip rule add 和ip rule del

android/external/iproute2/ip/Android.mk

android/external/iproute2/ip/iprule.c