MM-30970 Add Basic unreadMentions support for collapsed threads (#16407)

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>

store/retrylayer/retrylayer.go

@@ -8318,11 +8318,11 @@ func (s *RetryLayerThreadStore) CollectThreadsWithNewerReplies(userId string, ch
 
 }
 
-func (s *RetryLayerThreadStore) CreateMembershipIfNeeded(userId string, postId string, following bool) error {
+func (s *RetryLayerThreadStore) CreateMembershipIfNeeded(userId string, postId string, following bool, incrementMentions bool, updateFollowing bool) error {
 
 	tries := 0
 	for {
-		err := s.ThreadStore.CreateMembershipIfNeeded(userId, postId, following)
+		err := s.ThreadStore.CreateMembershipIfNeeded(userId, postId, following, incrementMentions, updateFollowing)
 		if err == nil {
 			return nil
 		}
@@ -8438,6 +8438,26 @@ func (s *RetryLayerThreadStore) GetMembershipsForUser(userId string) ([]*model.T
 
 }
 
+func (s *RetryLayerThreadStore) GetPosts(threadId string, since int64) ([]*model.Post, error) {
+
+	tries := 0
+	for {
+		result, err := s.ThreadStore.GetPosts(threadId, since)
+		if err == nil {
+			return result, nil
+		}
+		if !isRepeatableError(err) {
+			return result, err
+		}
+		tries++
+		if tries >= 3 {
+			err = errors.Wrap(err, "giving up after 3 consecutive repeatable transaction failures")
+			return result, err
+		}
+	}
+
+}
+
 func (s *RetryLayerThreadStore) GetThreadsForUser(userId string, opts model.GetUserThreadsOpts) (*model.Threads, error) {
 
 	tries := 0
@@ -8598,11 +8618,11 @@ func (s *RetryLayerThreadStore) UpdateMembership(membership *model.ThreadMembers
 
 }
 
-func (s *RetryLayerThreadStore) UpdateUnreadsByChannel(userId string, changedThreads []string, timestamp int64) error {
+func (s *RetryLayerThreadStore) UpdateUnreadsByChannel(userId string, changedThreads []string, timestamp int64, updateViewedTimestamp bool) error {
 
 	tries := 0
 	for {
-		err := s.ThreadStore.UpdateUnreadsByChannel(userId, changedThreads, timestamp)
+		err := s.ThreadStore.UpdateUnreadsByChannel(userId, changedThreads, timestamp, updateViewedTimestamp)
 		if err == nil {
 			return nil
 		}