Keep track of when a socket has been destroyed

sdk/lib/io/http_impl.dart

Index: sdk/lib/io/http_impl.dart
diff --git a/sdk/lib/io/http_impl.dart b/sdk/lib/io/http_impl.dart
index 4931831f86764d188263ec5eb74ea905b5d877e4..98a3cf9f5b093f1d2603299d3735274f6d2ef61b 100644
--- a/sdk/lib/io/http_impl.dart
+++ b/sdk/lib/io/http_impl.dart
@@ -1926,10 +1926,13 @@ class _HttpServer extends Stream<HttpRequest> implements HttpServer {
                                      cancelOnError: cancelOnError);
   }
 
-  void close() {
+  Future close() {
     closed = true;
+    Future result;
     if (_serverSocket != null && _closeServer) {
-      _serverSocket.close();
+      result = _serverSocket.close();
+    } else {
+      result = new Future.value();

[kustermann, 2013/07/18 11:34:46]

If somebody calls close() twice and once the future would complete with an
error, then the second time he should get the same future (which should complete
with the same error).

Is it guaranteed that we never get into an error situation?

[Anders Johnsen, 2013/07/19 10:49:07]

Yes, it'll never complete with an error.

     }
     if (_sessionManagerInstance != null) {
       _sessionManagerInstance.close();
@@ -1939,6 +1942,7 @@ class _HttpServer extends Stream<HttpRequest> implements HttpServer {
       connection.destroy();
     }
     _connections.clear();
+    return result;
   }
 
   int get port {