Regression from commit 9205b4eb09dcb4c91539e092db521154fc4e9523. On
conversion from odp or ppt to pptx, some slide layouts were not saved if
their masters were seen as equivalent.
When reducing duplicated masters, only the layouts used in the Impress
masters were saved for each duplicated masters. But when converting from
other formats that handle masters/layouts differently it's necessary to
search for all used layouts in each Impress slide that uses each
duplicated master.
Change-Id: Ie27852e7c0ff0b160a4e2415669f5e615c46e2f9
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/181030
Reviewed-on: https://gerrit.libreoffice.org/c/core/+/181070
Tested-by: Jenkins
Reviewed-by: Jaume Pujantell <jaume.pujantell@collabora.com>
76c6d180f3