Merge "Query Apn protocol by roaming state"

import android.provider.Settings;

import android.provider.Telephony.Carriers;

import android.telephony.CarrierConfigManager;

import android.telephony.ServiceState;

import android.telephony.SubscriptionManager;

import android.telephony.SubscriptionManager.OnSubscriptionsChangedListener;

import android.telephony.TelephonyManager;

        if (apn == null) {

            return APN_INVALID;

        }

        TelephonyManager phone = (TelephonyManager)

                mContext.getSystemService(Context.TELEPHONY_SERVICE);

        // Carrier configuration may override framework roaming state, we need to use the actual

        // modem roaming state instead of the framework roaming state.

        boolean isDataRoamingFromRegistration = phone.getServiceState().

                getDataRoamingFromRegistration();

        String projection = isDataRoamingFromRegistration ? Carriers.ROAMING_PROTOCOL :

                Carriers.PROTOCOL;

        String selection = String.format("current = 1 and apn = '%s' and carrier_enabled = 1", apn);

        Cursor cursor = null;

        try {

            cursor = mContext.getContentResolver().query(

                    Carriers.CONTENT_URI,

                    new String[]{Carriers.PROTOCOL},

                    new String[]{projection},

                    selection,

                    null,

                    Carriers.DEFAULT_SORT_ORDER);