private String getValueFromKey(ReadableMap item, String key) {
        return item.hasKey(key) ? item.getString(key) : "";
    }
Retrieves <code>contact</code> for contact, or <code>null</code> if not
available.

@param contactId contact identifier, <code>recordID</code>
android/src/main/java/com/rt2zz/reactnativecontacts/impl/ContactsManagerImpl.java