http: make the client "res" object gets the same domain as "req"

Fixes #4046.

lib/http.js

@@ -1412,6 +1412,12 @@ function parserOnIncomingClient(res, shouldKeepAlive) {
   var socket = this.socket;
   var req = socket._httpMessage;
 
+  // propogate "domain" setting...
+  if (req.domain && !res.domain) {
+    debug('setting "res.domain"');
+    res.domain = req.domain;
+  }
+
   debug('AGENT incoming response!');
 
   if (req.res) {

test/simple/test-http-client-response-domain.js

@@ -0,0 +1,65 @@
+// Copyright Joyent, Inc. and other Node contributors.
+//
+// Permission is hereby granted, free of charge, to any person obtaining a
+// copy of this software and associated documentation files (the
+// "Software"), to deal in the Software without restriction, including
+// without limitation the rights to use, copy, modify, merge, publish,
+// distribute, sublicense, and/or sell copies of the Software, and to permit
+// persons to whom the Software is furnished to do so, subject to the
+// following conditions:
+//
+// The above copyright notice and this permission notice shall be included
+// in all copies or substantial portions of the Software.
+//
+// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
+// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
+// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
+// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
+// USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+var common = require('../common'),
+    assert = require('assert'),
+    http = require('http'),
+    domain = require('domain');
+
+var gotDomainError = false;
+var d;
+
+process.on('exit', function() {
+  assert(gotDomainError);
+});
+
+// first fire up a simple HTTP server
+var server = http.createServer(function(req, res) {
+  res.writeHead(200);
+  res.end();
+  server.close();
+});
+server.listen(common.PIPE, function() {
+  // create a domain
+  d = domain.create();
+  d.run(test);
+});
+
+function test() {
+
+  d.on('error', function(err) {
+    gotDomainError = true;
+    assert.equal('should be caught by domain', err.message);
+  });
+
+  var req = http.get({
+    socketPath: common.PIPE,
+    headers: {'Content-Length':'1'},
+    method: 'POST',
+    path: '/'
+  });
+  req.on('response', function(res) {
+    res.on('end', function() {
+      res.emit('error', new Error('should be caught by domain'));
+    });
+  });
+  req.end();
+}