My fix for #24272, #23613, File not found when single file in a folder (#24800)
My fix for #24272, #23613, File not found when single file in a folder (#24800)

* Fixed group share searching for members of
multiple group. Issue #11808.

* Fixed group share searching, continued.

Avoid searching for empty group list in getItemSharedWithUser().
Broke tests in previous commit, #12030.

* Simler check for group count.

* Fix for https://github.com/owncloud/core/issues/24783 , described there

* Now it's #24272, 24783 was a duplicate. Previous change was also not very good. Now we don't create ZIP with a single file inside.

whitekiba/server,IljaN/core,endsguy/server,owncloud/core,cernbox/core,nextcloud/server,pixelipo/server,sharidas/core,cernbox/core,whitekiba/server,endsguy/server,nextcloud/server,pollopolea/core,nextcloud/server,jbicha/server,bluelml/core,sharidas/core,jbicha/server,pollopolea/core,cernbox/core,sharidas/core,pixelipo/server,xx621998xx/server,andreas-p/nextcloud-server,bluelml/core,whitekiba/server,xx621998xx/server,Ardinis/server,pixelipo/server,jbicha/server,owncloud/core,endsguy/server,michaelletzgus/nextcloud-server,endsguy/server,xx621998xx/server,michaelletzgus/nextcloud-server,xx621998xx/server,endsguy/server,michaelletzgus/nextcloud-server,whitekiba/server,bluelml/core,phil-davis/core,andreas-p/nextcloud-server,pmattern/server,whitekiba/server,sharidas/core,pixelipo/server,pmattern/server,Ardinis/server,IljaN/core,pmattern/server,bluelml/core,IljaN/core,sharidas/core,owncloud/core,owncloud/core,cernbox/core,pollopolea/core,jbicha/server,Ardinis/server,nextcloud/server,bluelml/core,pmattern/server,andreas-p/nextcloud-server,IljaN/core,michaelletzgus/nextcloud-server,xx621998xx/server,pollopolea/core,jbicha/server,pmattern/server,IljaN/core,Ardinis/server,andreas-p/nextcloud-server,owncloud/core,andreas-p/nextcloud-server,pollopolea/core,Ardinis/server,cernbox/core,pixelipo/server