src/vs/editor/common/services/markerDecorationsService.ts/MarkerDecorationsService/_onModelRemoved
class MarkerDecorationsService:	private _onModelRemoved(model: ITextModel): void {
		const markerDecorations = this._markerDecorations.get(model.uri);
		if (markerDecorations) {
			markerDecorations.dispose();
			this._markerDecorations.delete(model.uri);
		}

		// clean up markers for internal, transient models
		if (model.uri.scheme === Schemas.inMemory
			|| model.uri.scheme === Schemas.internal
			|| model.uri.scheme === Schemas.vscode) {
			if (this._markerService) {
				this._markerService.read({ resource: model.uri }).map(marker => marker.owner).forEach(owner => this._markerService.remove(owner, [model.uri]));
			}
		}
	}