src/vs/workbench/contrib/markers/browser/markersTreeViewer.ts/MarkersViewModel/add
class MarkersViewModel:	add(marker: Marker): void {
		if (!this.markersViewStates.has(marker.id)) {
			const viewModel = this.instantiationService.createInstance(MarkerViewModel, marker);
			const disposables: IDisposable[] = [viewModel];
			viewModel.multiline = this.multiline;
			viewModel.onDidChange(() => {
				if (!this.bulkUpdate) {
					this._onDidChange.fire(marker);
				}
			}, this, disposables);
			this.markersViewStates.set(marker.id, { viewModel, disposables });

			const markers = this.markersPerResource.get(marker.resource.toString()) || [];
			markers.push(marker);
			this.markersPerResource.set(marker.resource.toString(), markers);
		}
	}