No longer add username to the completion model in privateMessageReceived

The username is added to the completion model with the
"addRecentChatter" method instead

Moved "NameOptions" stuff from base class Channel to TwitchChannel where
it belongs

Remove unused Channel::getUsernamesForCompletions method

src/channel.cpp

@@ -79,25 +79,7 @@ void Channel::replaceMessage(messages::MessagePtr message, messages::MessagePtr
 
 void Channel::addRecentChatter(const std::shared_ptr<messages::Message> &message)
 {
-    assert(!message->loginName.isEmpty());
-
-    std::lock_guard<std::mutex> lock(this->recentChattersMutex);
-
-    this->recentChatters[message->loginName] = {message->displayName, message->localizedName};
-}
-
-std::vector<Channel::NameOptions> Channel::getUsernamesForCompletions()
-{
-    std::vector<NameOptions> names;
-
-    this->recentChattersMutex.lock();
-    for (const auto &p : this->recentChatters) {
-        names.push_back(p.second);
-    }
-    // usernames.insert(this->recentChatters.begin(), this->recentChatters.end());
-    this->recentChattersMutex.unlock();
-
-    return names;
+    // Do nothing by default
 }
 
 bool Channel::canSendMessage() const
@@ -118,4 +100,5 @@ std::shared_ptr<Channel> Channel::getEmpty()
 void Channel::onConnected()
 {
 }
+
 }  // namespace chatterino