Backport 1.8.4-1 from Disco to Bionic and Cosmic as a security update

[Amr Ibrahim]

Please backport 1.8.4-1 from Disco to Bionic and Cosmic as a security update. Debian 9 has already received 1.8.4 as a security update.

Upstream changelog:
    Add rdp_protocol_error function that is used in several fixes
    Refactor of process_bitmap_updates
    Fix possible integer overflow in s_check_rem() on 32bit arch
    Fix memory corruption in process_bitmap_data - CVE-2018-8794
    Fix remote code execution in process_bitmap_data - CVE-2018-8795
    Fix remote code execution in process_plane - CVE-2018-8797
    Fix Denial of Service in mcs_recv_connect_response - CVE-2018-20175
    Fix Denial of Service in mcs_parse_domain_params - CVE-2018-20175
    Fix Denial of Service in sec_parse_crypt_info - CVE-2018-20176
    Fix Denial of Service in sec_recv - CVE-2018-20176
    Fix minor information leak in rdpdr_process - CVE-2018-8791
    Fix Denial of Service in cssp_read_tsrequest - CVE-2018-8792
    Fix remote code execution in cssp_read_tsrequest - CVE-2018-8793
    Fix Denial of Service in process_bitmap_data - CVE-2018-8796
    Fix minor information leak in rdpsnd_process_ping - CVE-2018-8798
    Fix Denial of Service in process_secondary_order - CVE-2018-8799
    Fix remote code execution in in ui_clip_handle_data - CVE-2018-8800
    Fix major information leak in ui_clip_handle_data - CVE-2018-20174
    Fix memory corruption in rdp_in_unistr - CVE-2018-20177
    Fix Denial of Service in process_demand_active - CVE-2018-20178
    Fix remote code execution in lspci_process - CVE-2018-20179
    Fix remote code execution in rdpsnddbg_process - CVE-2018-20180
    Fix remote code execution in seamless_process - CVE-2018-20181
    Fix remote code execution in seamless_process_line - CVE-2018-20182
    Fix building against OpenSSL 1.1