Add getAvoidBadWifi system API

This helps remove the dependency on MultinetworkPolicyTracker from
IpClient.

Test: atest FrameworksNetTests NetworkStackTests
Bug: 112869080
Change-Id: If56791dbed564772f25a859f301b8b52d84e38a3

core/java/android/net/ConnectivityManager.java

@@ -3698,6 +3698,19 @@ public class ConnectivityManager {
         }
     }
 
+    /**
+     * Determine whether the device is configured to avoid bad wifi.
+     * @hide
+     */
+    @SystemApi
+    public boolean getAvoidBadWifi() {
+        try {
+            return mService.getAvoidBadWifi();
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
     /**
      * It is acceptable to briefly use multipath data to provide seamless connectivity for
      * time-sensitive user-facing operations when the system default network is temporarily

core/java/android/net/IConnectivityManager.aidl

@@ -165,6 +165,7 @@ interface IConnectivityManager
     void setAvoidUnvalidated(in Network network);
     void startCaptivePortalApp(in Network network);
 
+    boolean getAvoidBadWifi();
     int getMultipathPreference(in Network Network);
 
     NetworkRequest getDefaultRequest();

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

@@ -3183,6 +3183,15 @@ public class ConnectivityService extends IConnectivityManager.Stub
         return mMultinetworkPolicyTracker.getAvoidBadWifi();
     }
 
+    @Override
+    public boolean getAvoidBadWifi() {
+        if (!checkNetworkStackPermission()) {
+            throw new SecurityException("avoidBadWifi requires NETWORK_STACK permission");
+        }
+        return avoidBadWifi();
+    }
+
+
     private void rematchForAvoidBadWifiUpdate() {
         rematchAllNetworksAndRequests(null, 0);
         for (NetworkAgentInfo nai: mNetworkAgentInfos.values()) {