Multi-user - wallpaper service

- Allow each user to have their own wallpaper (live or static).
- Migrate old wallpaper on upgrade.
- Update SystemBackupAgent to backup/restore from primary user's
  new wallpaper directory.

Reduce dependency on Binder.getOrigCallingUser() by passing the
userId for bindService.

Change-Id: I19c8c3296d3d2efa7f28f951d4b84407489e2166
diff --git a/core/java/android/app/IActivityManager.java b/core/java/android/app/IActivityManager.java
index a62f724..7deb615 100644
--- a/core/java/android/app/IActivityManager.java
+++ b/core/java/android/app/IActivityManager.java
@@ -166,7 +166,7 @@
             int id, Notification notification, boolean keepNotification) throws RemoteException;
     public int bindService(IApplicationThread caller, IBinder token,
             Intent service, String resolvedType,
-            IServiceConnection connection, int flags) throws RemoteException;
+            IServiceConnection connection, int flags, int userId) throws RemoteException;
     public boolean unbindService(IServiceConnection connection) throws RemoteException;
     public void publishService(IBinder token,
             Intent intent, IBinder service) throws RemoteException;