Use resource instead of carrier config

The carrier config is not yet set correctly. In the future we can
finish the migration to the carrier config. This is tracked in
b/80541766.

Bug: 70309465
Bug: 80088968
Test: verified that Sprint does not show APNs and Verizon does
Change-Id: I04a1d60ce6ea264a9ca9a8a5456801ce179e98c6
diff --git a/src/com/android/phone/MobileNetworkSettings.java b/src/com/android/phone/MobileNetworkSettings.java
index 691d9ff..66c5650 100644
--- a/src/com/android/phone/MobileNetworkSettings.java
+++ b/src/com/android/phone/MobileNetworkSettings.java
@@ -1011,8 +1011,7 @@
                 // in case it is currently something else. That is possible if user
                 // changed the setting while roaming and is now back to home network.
                 settingsNetworkMode = preferredNetworkMode;
-            } else if (carrierConfig.getBoolean(
-                    CarrierConfigManager.KEY_WORLD_PHONE_BOOL) == true) {
+            } else if (isWorldMode()) {
                 prefSet.removePreference(mButtonEnabledNetworks);
                 // set the listener for the mButtonPreferredNetworkMode list preference so we can issue
                 // change Preferred Network Mode.
@@ -1898,6 +1897,7 @@
             return super.onOptionsItemSelected(item);
         }
 
+        // TODO: b/80541766 this should use the carrier config, not the resource overlay
         private boolean isWorldMode() {
             boolean worldModeOn = false;
             final String configString = getResources().getString(R.string.config_world_mode);