Do not throw exception when there is no tile for category.

    public synchronized DashboardCategory getTilesByCategory(Context context, String categoryKey) {

        tryInitCategories(context);

        final DashboardCategory category = mCategoryByKeyMap.get(categoryKey);

        if (category == null) {

            throw new IllegalStateException("Can't find category with key " + categoryKey);

        }

        return category;

        return mCategoryByKeyMap.get(categoryKey);

    }

    public synchronized List<DashboardCategory> getCategories(Context context) {