Reapply "Add onClosed callbacks to HTTP output streams""

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 9bf97008d3498a1c30634e8e53f8d1b1379b3bb7..08451ab61b03e7fe00b111f86b0c8f8b624203ac 100644
--- a/sdk/lib/io/http_impl.dart
+++ b/sdk/lib/io/http_impl.dart
@@ -500,6 +500,9 @@ class _HttpResponse extends _HttpRequestResponseBase implements HttpResponse {
     _writeDone();
     // Indicate to the connection that the response handling is done.
     _httpConnection._responseClosed();
+    if (_streamClosedHandler != null) {
+      new Timer(0, (_) => _streamClosedHandler());
+    }
   }
 
   void _streamSetNoPendingWriteHandler(callback()) {
@@ -508,8 +511,8 @@ class _HttpResponse extends _HttpRequestResponseBase implements HttpResponse {
     }
   }
 
-  void _streamSetCloseHandler(callback()) {
-    // TODO(sgjesse): Handle this.
+  void _streamSetClosedHandler(callback()) {
+    _streamClosedHandler = callback;
   }
 
   void _streamSetErrorHandler(callback(e)) {
@@ -621,6 +624,7 @@ class _HttpResponse extends _HttpRequestResponseBase implements HttpResponse {
   int _statusCode;  // Response status code.
   String _reasonPhrase;  // Response reason phrase.
   _HttpOutputStream _outputStream;
+  Function _streamClosedHandler;
   Function _streamErrorHandler;
 }
 
@@ -699,7 +703,7 @@ class _HttpOutputStream extends _BaseOutputStream implements OutputStream {
   }
 
   void set onClosed(void callback()) {
-    _requestOrResponse._streamSetCloseHandler(callback);
+    _requestOrResponse._streamSetClosedHandler(callback);
   }
 
   void set onError(void callback(e)) {
@@ -1199,6 +1203,9 @@ class _HttpClientRequest
     // Ensure that any trailing data is written.
     _writeDone();
     _connection._requestClosed();
+    if (_streamClosedHandler != null) {
+      new Timer(0, (_) => _streamClosedHandler());
+    }
   }
 
   void _streamSetNoPendingWriteHandler(callback()) {
@@ -1207,8 +1214,8 @@ class _HttpClientRequest
     }
   }
 
-  void _streamSetCloseHandler(callback()) {
-    // TODO(sgjesse): Handle this.
+  void _streamSetClosedHandler(callback()) {
+    _streamClosedHandler = callback;
   }
 
   void _streamSetErrorHandler(callback(e)) {
@@ -1265,6 +1272,7 @@ class _HttpClientRequest
   Uri _uri;
   _HttpClientConnection _connection;
   _HttpOutputStream _outputStream;
+  Function _streamClosedHandler;
   Function _streamErrorHandler;
   bool _emptyBody = true;
 }