Revert "Erase queued commands when another command is about to be queued."

This reverts commit 604205045f.

src/terraform_gui.cpp

@@ -656,7 +656,6 @@ struct ScenarioEditorLandscapeGenerationWindow : Window {
 
 	virtual void OnPlaceObject(Point pt, TileIndex tile)
 	{
-		EraseQueuedTouchCommand();
 		switch (this->last_user_action) {
 			case WID_ETT_DEMOLISH: // Demolish aka dynamite button
 				PlaceProc_DemolishArea(tile);