src/vs/editor/browser/viewParts/contentWidgets/contentWidgets.ts/ViewContentWidgets/onBeforeRender
class ViewContentWidgets:	public onBeforeRender(viewportData: ViewportData): void {
		const keys = Object.keys(this._widgets);
		for (const widgetId of keys) {
			this._widgets[widgetId].onBeforeRender(viewportData);
		}
	}