...by removing explicitly user-provided functions that do the same as their
implicitly-defined counterparts, but whose presence may prevent implicitly
declared copy functions from being defined as non-deleted in the future

Change-Id: Ie9b943af57bd8081c06a531fb3c634e52f0a99b6
Reviewed-on: https://gerrit.libreoffice.org/58048
Tested-by: Jenkins
Reviewed-by: Stephan Bergmann <sbergman@redhat.com>