fix(MessagesCountNotifier): avoid pure virtual call

src/components/core/CoreManager.cpp

@@ -62,7 +62,10 @@ CoreManager::CoreManager (QObject *parent, const QString &configPath) :
   CoreHandlers *coreHandlers = mHandlers.get();
 
   QObject::connect(coreHandlers, &CoreHandlers::coreStarted, this, [] {
-    new MessagesCountNotifier(mInstance);
+    {
+      MessagesCountNotifier *messagesCountNotifier = new MessagesCountNotifier(mInstance);
+      messagesCountNotifier->updateUnreadMessagesCount();
+    }
 
     mInstance->mCallsListModel = new CallsListModel(mInstance);
     mInstance->mContactsListModel = new ContactsListModel(mInstance);

src/components/core/messages-count-notifier/AbstractMessagesCountNotifier.cpp

@@ -38,14 +38,10 @@ AbstractMessagesCountNotifier::AbstractMessagesCountNotifier (QObject *parent) :
     coreManager->getHandlers().get(), &CoreHandlers::messageReceived,
     this, &AbstractMessagesCountNotifier::handleMessageReceived
   );
-
-  updateUnreadMessagesCount();
 }
 
 // -----------------------------------------------------------------------------
 
-void AbstractMessagesCountNotifier::notifyUnreadMessagesCount (int) {}
-
 void AbstractMessagesCountNotifier::updateUnreadMessagesCount () {
   mUnreadMessagesCount = 0;
   for (const auto &chatRoom : CoreManager::getInstance()->getCore()->getChatRooms())

src/components/core/messages-count-notifier/AbstractMessagesCountNotifier.hpp

@@ -39,11 +39,12 @@ public:
   AbstractMessagesCountNotifier (QObject *parent = Q_NULLPTR);
   virtual ~AbstractMessagesCountNotifier () = default;
 
+  void updateUnreadMessagesCount ();
+
 protected:
   virtual void notifyUnreadMessagesCount (int n) = 0;
 
 private:
-  void updateUnreadMessagesCount ();
   void internalNotifyUnreadMessagesCount ();
 
   void handleChatModelCreated (const std::shared_ptr<ChatModel> &chatModel);