Refresh user list a little more eagerly

Unfortunately, we don't get a signal when user restrictions such as
for adding new users change. That means the user switcher UI could get
out of sync and showed the add user option when in fact it couldn't add one.

Also cleans up an unused method.

Bug: 18292723
Change-Id: I56f6f848d967d9d1c11bd6262eacbdb11f90cfe2
diff --git a/packages/SystemUI/src/com/android/systemui/qs/tiles/UserDetailView.java b/packages/SystemUI/src/com/android/systemui/qs/tiles/UserDetailView.java
index c524edc..6bad652 100644
--- a/packages/SystemUI/src/com/android/systemui/qs/tiles/UserDetailView.java
+++ b/packages/SystemUI/src/com/android/systemui/qs/tiles/UserDetailView.java
@@ -47,6 +47,10 @@
         ViewGroupAdapterBridge.link(this, mAdapter);
     }
 
+    public void refreshAdapter() {
+        mAdapter.refresh();
+    }
+
     public static class Adapter extends UserSwitcherController.BaseUserAdapter
             implements OnClickListener {