src/vs/workbench/contrib/mergeEditor/browser/commands/commands.ts/SetColumnLayout/constructor
class SetColumnLayout:	constructor() {
		super({
			id: 'merge.columnLayout',
			title: { value: localize('layout.column', "Column Layout"), original: 'Column Layout' },
			toggled: ctxMergeEditorLayout.isEqualTo('columns'),
			menu: [{
				id: MenuId.EditorTitle,
				when: ctxIsMergeEditor,
				group: '1_merge',
				order: 10,
			}],
			precondition: ctxIsMergeEditor,
		});
	}