DO NOT MERGE: Fix ConnectivityController meteredness checks

This patch corrects ConnectivityController's meteredness checks to
perform correct meteredness checks while VPNs are running. This fixes a
bug in O-MR1 where any apps using the DownloadProvider with unmetered
network constraints fail to start while the VPN is enabled.

This change adds a bespoke method for ConnectivityController, allowing
it to correctly identify the meteredness without affecting public API
surfaces.

Bug: 78644887
Test: Built, flashed on Walleye, and tested.
Test: Additional test coverage in subsequent patch(es).
Change-Id: Ie1d11d93d51d936ce81cd5984af61bde30325983

core/java/android/net/ConnectivityManager.java

@@ -2504,6 +2504,28 @@ public class ConnectivityManager {
         }
     }
 
+    /**
+     * Returns if the active data network for the given UID is metered. A network
+     * is classified as metered when the user is sensitive to heavy data usage on
+     * that connection due to monetary costs, data limitations or
+     * battery/performance issues. You should check this before doing large
+     * data transfers, and warn the user or delay the operation until another
+     * network is available.
+     *
+     * @return {@code true} if large transfers should be avoided, otherwise
+     *        {@code false}.
+     *
+     * @hide
+     */
+    @RequiresPermission(android.Manifest.permission.CONNECTIVITY_INTERNAL)
+    public boolean isActiveNetworkMeteredForUid(int uid) {
+        try {
+            return mService.isActiveNetworkMeteredForUid(uid);
+        } catch (RemoteException e) {
+            throw e.rethrowFromSystemServer();
+        }
+    }
+
     /**
      * If the LockdownVpn mechanism is enabled, updates the vpn
      * with a reload of its profile.

core/java/android/net/IConnectivityManager.aidl

@@ -66,6 +66,7 @@ interface IConnectivityManager
 
     NetworkQuotaInfo getActiveNetworkQuotaInfo();
     boolean isActiveNetworkMetered();
+    boolean isActiveNetworkMeteredForUid(int uid);
 
     boolean requestRouteToHostAddress(int networkType, in byte[] hostAddress);
 

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

@@ -1339,7 +1339,17 @@ public class ConnectivityService extends IConnectivityManager.Stub
     public boolean isActiveNetworkMetered() {
         enforceAccessPermission();
 
-        final int uid = Binder.getCallingUid();
+        return isActiveNetworkMeteredCommon(Binder.getCallingUid());
+    }
+
+    @Override
+    public boolean isActiveNetworkMeteredForUid(int uid) {
+        enforceConnectivityInternalPermission();
+
+        return isActiveNetworkMeteredCommon(uid);
+    }
+
+    private boolean isActiveNetworkMeteredCommon(int uid) {
         final NetworkCapabilities caps = getUnfilteredActiveNetworkState(uid).networkCapabilities;
         if (caps != null) {
             return !caps.hasCapability(NetworkCapabilities.NET_CAPABILITY_NOT_METERED);