messageListModel: improve load time

Change-Id: Ica33126a1d75b4880c70c1e7f654f82db6499bbd

src/libclient/messagelistmodel.cpp

@@ -417,8 +417,11 @@ MessageListModel::isOnlyEmoji(const QString& text) const
 QVariant
 MessageListModel::dataForItem(item_t item, int, int role) const
 {
-    auto replyId = item.second.commit["reply-to"];
-    auto repliedMsg = getIndexOfMessage(replyId);
+    QString replyId = item.second.commit["reply-to"];
+    int repliedMsg;
+    if (!replyId.isEmpty() && (role == Role::ReplyToAuthor || role == Role::ReplyToBody)) {
+        repliedMsg = getIndexOfMessage(replyId);
+    }
     switch (role) {
     case Role::Id:
         return QVariant(item.first);