Fix opening message menus for popup windows

We were previously assuming that we always want to parent these menus to
RoomPage, but that only exists on the main window. If you tried to open
the menu for say - the search window - then it would confusingly still
open on the main menu.

Thankfully the way to fix this is simple, by passing a parent QtObject
around.

src/messagecontent/CodeComponent.qml

@@ -132,7 +132,7 @@ QQC2.Control {
                 acceptedDevices: PointerDevice.TouchScreen
                 onLongPressed: {
                     const event = root.Message.room.findEvent(root.eventId);
-                    RoomManager.viewEventMenu(event, root.Message.room, root.Message.selectedText, root.Message.hoveredLink);
+                    RoomManager.viewEventMenu(root.QQC2.Overlay.overlay, event, root.Message.room, root.Message.selectedText, root.Message.hoveredLink);
                 }
             }