read preferhms value from manifest metadata

This value defaults to false (prefer gms)

Author: emawby

OneSignalSDK/onesignal/src/main/java/com/onesignal/OSUtils.java

@@ -77,6 +77,7 @@
 class OSUtils {
 
    public static final int UNINITIALIZABLE_STATUS = -999;
+   private static final String PREFER_HMS_METADATA_NAME = "com.onesignal.preferHMS";
 
    public static int MAX_NETWORK_REQUEST_ATTEMPT_COUNT = 3;
    static final int[] NO_RETRY_NETWROK_REQUEST_STATUS_CODES = {401, 402, 403, 404, 410};
@@ -369,7 +370,8 @@ int getDeviceType() {
       if (supportsADM())
          return UserState.DEVICE_TYPE_FIREOS;
 
-      boolean preferHMS = false;
+      Context context = OneSignal.appContext;
+      boolean preferHMS = context != null && OSUtils.getManifestMetaBoolean(context, PREFER_HMS_METADATA_NAME);
       boolean supportsHMS = supportsHMS();
       boolean supportsFCM = supportsGooglePush();