extensions/typescript-language-features/web/webServer.ts/WorkerSession/constructor
class WorkerSession:		constructor() {
			super(
				ts.sys as ts.server.ServerHost & { tryEnableSourceMapsForHost?(): void; getEnvironmentVariable(name: string): string },
				{ writeMessage },
				options,
				logger,
				cancellationToken,
				hrtime);
		}