function clearPendingQuery() {
        if (_pendingQuery) {
            clearTimeout(_pendingQuery);
            _pendingQuery = undefined;
        }
    }
Register an inline query.

@param {object} args `url`: string or function, the dictionary service url or a function to return the dictionary service url, `parseResult`: function, a function to parse result from dictionary service and return a HTML string to render explanation, `headers`: object[optional], in case your dictionary service needs authentication.
@name Front.registerInlineQuery

@see [example](https://github.com/brookhong/Surfingkeys/wiki/Register-inline-query).