From ticket #3116: fix possible segfault when freeing a VFS.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
From ticket #3116: fix segfault in cpio VFS while reading corrupted RPM.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
From ticket #3116: attempt to fix segfault while passing messages to widgets.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>