Merge "Following commit for asynchronous DNS query API"

 * POSIX error code (see errno.h) if an immediate error occurs.

 */

int android_res_nsend(net_handle_t network,

        const unsigned char *msg, int msglen) __INTRODUCED_IN(29);

        const uint8_t *msg, size_t msglen) __INTRODUCED_IN(29);

/**

 * Read a result for the query associated with the |fd| descriptor.

 *     >= 0: length of |answer|. |rcode| is the resolver return code (e.g., ns_r_nxdomain)

 */

int android_res_nresult(int fd,

        int *rcode, unsigned char *answer, int anslen) __INTRODUCED_IN(29);

        int *rcode, uint8_t *answer, size_t anslen) __INTRODUCED_IN(29);

/**

 * Attempts to cancel the in-progress query associated with the |nsend_fd|