src/vs/workbench/contrib/markers/browser/markersModel.ts/ResourceMarkers/delete
class ResourceMarkers:	delete(uri: URI) {
		const array = this._markersMap.get(uri);
		if (array) {
			this._total -= array.length;
			this._cachedMarkers = undefined;
			this._markersMap.delete(uri);
		}
	}