Call DataSettingsManager to determine dafault data roaming in PIM

This cl replaces a internal private method in PhoneInterfaceManager
with calling DataSettingsManager.isDefaultDataRoamingEnabled to
determine the default data roaming value when resetting telephony.

It removes the duplication logic and possible inconsistency.

Bug: 136008634
Test: FrameworksTelephonyTests
Test: Telephony factory reset
Flag: EXEMPT (minior refactor without logic change)
Change-Id: Ia1316794f2c915804e48f6b119ff907c1a1dd60e
diff --git a/src/com/android/phone/PhoneInterfaceManager.java b/src/com/android/phone/PhoneInterfaceManager.java
index 839d8cb..e18818c 100644
--- a/src/com/android/phone/PhoneInterfaceManager.java
+++ b/src/com/android/phone/PhoneInterfaceManager.java
@@ -8504,7 +8504,8 @@
                 setNetworkSelectionModeAutomatic(subId);
                 Phone phone = getPhone(subId);
                 cleanUpAllowedNetworkTypes(phone, subId);
-                setDataRoamingEnabled(subId, getDefaultDataRoamingEnabled(subId));
+                setDataRoamingEnabled(subId, phone == null ? false
+                        : phone.getDataSettingsManager().isDefaultDataRoamingEnabled());
                 getPhone(subId).resetCarrierKeysForImsiEncryption();
             }
             // There has been issues when Sms raw table somehow stores orphan
@@ -10107,20 +10108,6 @@
     }
 
     /**
-     * Returns true if the data roaming is enabled by default, i.e the system property
-     * of {@link #DEFAULT_DATA_ROAMING_PROPERTY_NAME} is true or the config of
-     * {@link CarrierConfigManager#KEY_CARRIER_DEFAULT_DATA_ROAMING_ENABLED_BOOL} is true.
-     */
-    private boolean getDefaultDataRoamingEnabled(int subId) {
-        final CarrierConfigManager configMgr = (CarrierConfigManager)
-                mApp.getSystemService(Context.CARRIER_CONFIG_SERVICE);
-        boolean isDataRoamingEnabled = TelephonyProperties.data_roaming().orElse(false);
-        isDataRoamingEnabled |= configMgr.getConfigForSubId(subId).getBoolean(
-                CarrierConfigManager.KEY_CARRIER_DEFAULT_DATA_ROAMING_ENABLED_BOOL);
-        return isDataRoamingEnabled;
-    }
-
-    /**
      * Returns the default network type for the given {@code subId}, if the default network type is
      * not set, return {@link Phone#PREFERRED_NT_MODE}.
      */