src/vs/workbench/api/common/extHostDiagnostics.ts/DiagnosticCollection/constructor
class DiagnosticCollection:	constructor(
		private readonly _name: string,
		private readonly _owner: string,
		private readonly _maxDiagnosticsPerFile: number,
		extUri: IExtUri,
		proxy: MainThreadDiagnosticsShape | undefined,
		onDidChangeDiagnostics: Emitter<vscode.Uri[]>
	) {
		this.#data = new ResourceMap(uri => extUri.getComparisonKey(uri));
		this.#proxy = proxy;
		this.#onDidChangeDiagnostics = onDidChangeDiagnostics;
	}