src/vs/workbench/contrib/mergeEditor/browser/commands/commands.ts/SetMixedLayout/constructor
class SetMixedLayout:	constructor() {
		super({
			id: 'merge.mixedLayout',
			title: {
				value: localize('layout.mixed', 'Mixed Layout'),
				original: 'Mixed Layout',
			},
			toggled: ctxMergeEditorLayout.isEqualTo('mixed'),
			menu: [
				{
					id: MenuId.EditorTitle,
					when: ctxIsMergeEditor,
					group: '1_merge',
					order: 9,
				},
			],
			precondition: ctxIsMergeEditor,
		});
	}