The controller needs to fill its caches before it starts binding/recycling/
deleting or provisioning volumes and claims. This was done using blocking
initial 'xxx added' from going through syncClaim/syncVolume. However, when
the caches were full, the controller waited for the next sync period to do
actual binding/recycling etc.
In this patch, the controller fills its caches directly from etcd and then
processes initial 'xxx added' events to reconcile the world and bind/recycle/
delete/provision stuff, resulting in faster binding after startup.
Fixes#25967 (properly)
df161c3a7e