Add getLanguage to StateSynchronizers

* Add getLanguage to OneSignalStateSynchronizer and UserStatePushSynchronizer

Author: tanaynigam

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

@@ -183,6 +183,10 @@ static void setSubscription(boolean enable) {
    static boolean getUserSubscribePreference() {
       return getPushStateSynchronizer().getUserSubscribePreference();
    }
+
+   static String getLanguage() {
+      return getPushStateSynchronizer().getLanguage();
+   }
 
    static void setPermission(boolean enable) {
       getPushStateSynchronizer().setPermission(enable);

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

@@ -158,6 +158,10 @@ public boolean getUserSubscribePreference() {
         return getToSyncUserState().getDependValues().optBoolean(USER_SUBSCRIBE_PREF, true);
     }
 
+    public String getLanguage() {
+        return  getToSyncUserState().getDependValues().optString(LANGUAGE, null);
+    }
+
     @Override
     public void setPermission(boolean enable) {
         try {