Generate an error for active connections when the HTTP client is shutdown

tests/standalone/io/http_content_length_test.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 //
 
 #import("dart:isolate");
 #import("dart:io");
 
 void testNoBody(int totalConnections, bool explicitContentLength) {
   HttpServer server = new HttpServer();
@@ skipping 20 matching lines @@
         request.contentLength = 0;
         Expect.throws(() => stream.writeString("x"), (e) => e is HttpException);
       }
       stream.close();
       Expect.throws(() => stream.writeString("x"), (e) => e is HttpException);
     };
     conn.onResponse = (HttpClientResponse response) {
       Expect.equals("0", response.headers.value('content-length'));
       Expect.equals(0, response.contentLength);
       count++;
-      if (count == totalConnections) {
-        client.shutdown();
-        server.close();
-      }
+      response.inputStream.onData = response.inputStream.read;
+      response.inputStream.onClosed = () {
+        if (count == totalConnections) {
+          client.shutdown();
+          server.close();
+        }
+      };
     };
   }
 }
 
 void testBody(int totalConnections) {
   HttpServer server = new HttpServer();
   server.onError = (e) => Expect.fail("Unexpected error $e");
   server.listen("127.0.0.1", 0, backlog: totalConnections);
   server.defaultRequestHandler = (HttpRequest request, HttpResponse response) {
     Expect.equals("2", request.headers.value('content-length'));
@@ skipping 20 matching lines @@
       Expect.throws(() => request.contentLength = 3, (e) => e is HttpException);
       stream.writeString("x");
       Expect.throws(() => stream.writeString("x"), (e) => e is HttpException);
       stream.close();
       Expect.throws(() => stream.writeString("x"), (e) => e is HttpException);
     };
     conn.onResponse = (HttpClientResponse response) {
       Expect.equals("2", response.headers.value('content-length'));
       Expect.equals(2, response.contentLength);
       count++;
-      if (count == totalConnections) {
-        client.shutdown();
-        server.close();
-      }
+      response.inputStream.onData = response.inputStream.read;
+      response.inputStream.onClosed = () {
+        if (count == totalConnections) {
+          client.shutdown();
+          server.close();
+        }
+      };
     };
   }
 }
 
 void testHttp10() {
   HttpServer server = new HttpServer();
   server.onError = (e) => Expect.fail("Unexpected error $e");
   server.listen("127.0.0.1", 0, backlog: 5);
   server.defaultRequestHandler = (HttpRequest request, HttpResponse response) {
     Expect.isNull(request.headers.value('content-length'));
@@ skipping 16 matching lines @@
     };
   };
 }
 
 void main() {
   testNoBody(5, false);
   testNoBody(5, true);
   testBody(5);
   testHttp10();
 }