...when implicit special member functions are defined for FWE_DLLPUBLIC
MergeMenuInstruction etc.

Change-Id: Ida796edaea73cf2c918feee1ee961e2065f25ee8
Reviewed-on: https://gerrit.libreoffice.org/68376
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>