/// <summary>
        /// Enables HttpClient and HttpWebRequest instrumentation.
        /// </summary>
        /// <param name="builder"><see cref="TracerProviderBuilder"/> being configured.</param>
        /// <param name="configureHttpClientInstrumentationOptions">HttpClient configuration options.</param>
        /// <returns>The instance of <see cref="TracerProviderBuilder"/> to chain the calls.</returns>
        public static TracerProviderBuilder AddHttpInstrumentation(
            this TracerProviderBuilder builder,
            Action <HttpClientInstrumentationOptions> configureHttpClientInstrumentationOptions = null)
        {
            if (builder == null)
            {
                throw new ArgumentNullException(nameof(builder));
            }

            builder.AddHttpClientInstrumentation(configureHttpClientInstrumentationOptions);
#if NETFRAMEWORK
            builder.AddHttpWebRequestInstrumentation();
#endif
            return(builder);
        }