ChannelStore migration Part 2 (#15405)

* Migration completed

* Several corrections in tests

* Fix imports

* Fix some errors after testing

* Trigger CI

* Fix tests

* Suggestions

* Suggestions

* Add license

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

app/notification.go

@@ -4,6 +4,7 @@
 package app
 
 import (
+	"net/http"
 	"sort"
 	"strings"
 	"unicode"
@@ -32,7 +33,7 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 	cmnchan := make(chan store.StoreResult, 1)
 	go func() {
 		props, err := a.Srv().Store.Channel().GetAllChannelMembersNotifyPropsForChannel(channel.Id, true)
-		cmnchan <- store.StoreResult{Data: props, Err: err}
+		cmnchan <- store.StoreResult{Data: props, NErr: err}
 		close(cmnchan)
 	}()
 
@@ -63,8 +64,8 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 	profileMap := result.Data.(map[string]*model.User)
 
 	result = <-cmnchan
-	if result.Err != nil {
-		return nil, result.Err
+	if result.NErr != nil {
+		return nil, result.NErr
 	}
 	channelMemberNotifyPropsMap := result.Data.(map[string]model.StringMap)
 
@@ -164,7 +165,13 @@ func (a *App) SendNotifications(post *model.Post, team *model.Team, channel *mod
 
 		umc := make(chan *model.AppError, 1)
 		go func(userId string) {
-			umc <- a.Srv().Store.Channel().IncrementMentionCount(post.ChannelId, userId)
+			nErr := a.Srv().Store.Channel().IncrementMentionCount(post.ChannelId, userId)
+			if nErr != nil {
+				umc <- model.NewAppError("SendNotifications", "app.channel.increment_mention_count.app_error", nil, nErr.Error(), http.StatusInternalServerError)
+			} else {
+				umc <- nil
+			}
+
 			close(umc)
 		}(id)
 		updateMentionChans = append(updateMentionChans, umc)