finalCallback = (err, compilation) => {
			this.running = false;
			this.compiler.running = false;
			this.compiler.watching = undefined;
			this.compiler.watchMode = false;
			this.compiler.modifiedFiles = undefined;
			this.compiler.removedFiles = undefined;
			this.compiler.fileTimestamps = undefined;
			this.compiler.contextTimestamps = undefined;
			this.compiler.fsStartTime = undefined;
			/**
			 * @param {WebpackError | null} err error if any
			 */
			const shutdown = err => {
				this.compiler.hooks.watchClose.call();
				const closeCallbacks =
					/** @type {Callback<void>[]} */
					(this._closeCallbacks);
				this._closeCallbacks = undefined;
				for (const cb of closeCallbacks) cb(err);
			};
			if (compilation) {
				const logger = compilation.getLogger("webpack.Watching");
				logger.time("storeBuildDependencies");
				this.compiler.cache.storeBuildDependencies(
					compilation.buildDependencies,
					err2 => {
						logger.timeEnd("storeBuildDependencies");
						shutdown(err || err2);
					}
				);
			} else {
				shutdown(err);
			}
		}
@param {WebpackError | null} err error if any
@param {Compilation=} compilation compilation if any