public CallLogAdapterHelper(
      Context context,
      Callback cb,
      ContactInfoHelper contactInfoHelper,
      PhoneNumberDisplayHelper phoneNumberHelper) {
    mContext = context;
    mCb = cb;
    mContactInfoHelper = contactInfoHelper;
    mPhoneNumberDisplayHelper = phoneNumberHelper;

    mContactInfoCache = ExpirableCache.create(CONTACT_INFO_CACHE_SIZE);
    mRequests = new LinkedList<ContactInfoRequest>();
  }