Added test that verifies that the host header is correctly

overwritten by a user-provided value.

jetty-client/src/test/java/org/eclipse/jetty/client/HttpClientTest.java

@@ -1051,4 +1051,26 @@ public class HttpClientTest extends AbstractHttpClientServerTest
         Assert.assertArrayEquals(content, listener.getContent());
         Assert.assertArrayEquals(content, response.getContent());
     }
+
+    @Test
+    public void testCustomHostHeader() throws Exception
+    {
+        final String host = "localhost";
+        start(new AbstractHandler()
+        {
+            @Override
+            public void handle(String target, org.eclipse.jetty.server.Request baseRequest, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException
+            {
+                baseRequest.setHandled(true);
+                Assert.assertEquals(host, request.getServerName());
+            }
+        });
+
+        ContentResponse response = client.newRequest("http://127.0.0.1:" + connector.getLocalPort() + "/path")
+                .scheme(scheme)
+                .header(HttpHeader.HOST, host)
+                .send();
+
+        Assert.assertEquals(200, response.getStatus());
+    }
 }