The gossiper checks if features should be enabled from its timer
callback when it detects that endpoint_state_map changed, that is
different than shadow_endpoint_state_map.
shadow_endpoint_state_map is also assigned from endpoint_state_map in
storage_service::replicate_tm_and_ep_map(), called from
storage_service::on_change()
Call gossiper:maybe_enable_features() in replicate_tm_and_ep_map so
that we won't miss gossip feature update.
Fixes#2824
* git@github.com:scylladb/seastar-dev asias/gossip_miss_feature_update_v1:
gossip: Move the _features_condvar signal code to
maybe_enable_features
gossip: Make maybe_enable_features public
storage_service: Check gossip feature update in
replicate_tm_and_ep_map
(cherry picked from commit 02d41864af)
09da4f3d08