EXT-7729 WIP LLWARNS: Tons of "Making dummy class..." warnings on startup

indra/llui/llmenugl.cpp

indra/llui/llmenugl.h

indra/llui/llpanel.cpp

indra/llui/llui.cpp

indra/llui/lluictrlfactory.cpp

indra/llui/lluictrlfactory.h

indra/newview/llpanelnearbymedia.cpp

indra/newview/llstatusbar.cpp

indra/newview/llstatusbar.h

indra/newview/skins/default/xui/en/menu_edit.xml

indra/newview/skins/default/xui/en/panel_main_inventory.xml

indra/newview/skins/default/xui/en/panel_people.xml

indra/newview/skins/default/xui/en/panel_picks.xml

indra/newview/skins/default/xui/en/panel_toast.xml

indra/newview/skins/default/xui/en/sidepanel_task_info.xml

indra/newview/skins/paths.xml