src/vs/workbench/browser/parts/views/viewsService.ts/getPaneCompositeExtension
function getPaneCompositeExtension(viewContainerLocation: ViewContainerLocation): string {
	switch (viewContainerLocation) {
		case ViewContainerLocation.AuxiliaryBar:
			return PaneCompositeExtensions.Auxiliary;
		case ViewContainerLocation.Panel:
			return PaneCompositeExtensions.Panels;
		case ViewContainerLocation.Sidebar:
		default:
			return PaneCompositeExtensions.Viewlets;
	}
}