MM: Don't adapt the view when saving dbg documents

DoSaveCompleted updates the SwViewShell and recent file lists after
the document was saved via DoSaveAs. So we can simply drop the
call and delete the SfxMedium to save a copy.

Change-Id: I04a0710949ca60e1ff4cab24c6b504deb130db63
Reviewed-on: https://gerrit.libreoffice.org/10983
Reviewed-by: Michael Stahl <mstahl@redhat.com>
Tested-by: Michael Stahl <mstahl@redhat.com>