src/vs/editor/browser/view/viewOverlays.ts/MarginViewOverlays/constructor
class MarginViewOverlays:	constructor(context: ViewContext) {
		super(context);

		const options = this._context.configuration.options;
		const layoutInfo = options.get(EditorOption.layoutInfo);
		this._contentLeft = layoutInfo.contentLeft;

		this.domNode.setClassName('margin-view-overlays');
		this.domNode.setWidth(1);

		applyFontInfo(this.domNode, options.get(EditorOption.fontInfo));
	}