sys user split: first pass updating Settings

Update various places in Settings to use "admin" ueser flag
instead of checking user id "0".  This should be no-op in
single user mode since the only admin user would be user 0.
In split system user mode, this will correctly ACL admin
user instead of non-interactive system user.

Bug: 19913735
Change-Id: Ida4d59c5f689ea0dc34b3b3ff0822b087fa0afd6

src/com/android/settings/WirelessSettings.java

@@ -439,8 +439,7 @@ public class WirelessSettings extends SettingsPreferenceFragment implements Inde
                 result.add(KEY_TOGGLE_NSD);
 
                 final UserManager um = (UserManager) context.getSystemService(Context.USER_SERVICE);
-                final int myUserId = UserHandle.myUserId();
-                final boolean isSecondaryUser = myUserId != UserHandle.USER_OWNER;
+                final boolean isSecondaryUser = !um.isAdminUser();
                 final boolean isWimaxEnabled = !isSecondaryUser
                         && context.getResources().getBoolean(
                         com.android.internal.R.bool.config_wimaxEnabled);