cubicweb #5753543 storage broken due to merged cnx/req entity caches [validation pending]

Since 3.21.0, there is a unified entity cache on Connection instead of separate client-side and repo-side caches. Unfortunately, this means the _cw attribute for cached objects may be a web request or a connection; for most users this doesn't matter, but bfss storage accesses entity._cw.repo, which only exists if _cw is a Connection (it also calls Operation.get_instance(entity._cw), which has the same restriction).

priorityimportant
typebug
done in3.21.1
load1.000
load left0.000
closed by#d4bd28d5fca8 [server/sources] make sure entity._cw is a Connection before calling Storages
patch[server/sources] make sure entity._cw is a Connection before calling Storages [applied]