Fix Roomlist Shortcuts

Fix the ctrl + pgup/pgdwn shortcuts for the room list so that they work with tree model

BUG: 485949
(cherry picked from commit 28c9d94457)

src/models/sortfilterroomtreemodel.cpp

@@ -205,4 +205,14 @@ void SortFilterRoomTreeModel::setMode(SortFilterRoomTreeModel::Mode mode)
     invalidate();
 }
 
+QModelIndex SortFilterRoomTreeModel::currentRoomIndex() const
+{
+    const auto roomModel = dynamic_cast<RoomTreeModel *>(sourceModel());
+    if (roomModel == nullptr) {
+        return {};
+    }
+
+    return mapFromSource(roomModel->indexForRoom(RoomManager::instance().currentRoom()));
+}
+
 #include "moc_sortfilterroomtreemodel.cpp"

src/models/sortfilterroomtreemodel.h

@@ -76,6 +76,8 @@ public:
     Mode mode() const;
     void setMode(Mode mode);
 
+    Q_INVOKABLE QModelIndex currentRoomIndex() const;
+
 protected:
     /**
      * @brief Returns true if the value of source_left is less than source_right.