419901 - Client always adds extra user-agent header.

Added test case.

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

@@ -28,7 +28,9 @@ import java.nio.channels.UnresolvedAddressException;
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.nio.file.Paths;
+import java.util.ArrayList;
 import java.util.Arrays;
+import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 import java.util.NoSuchElementException;
@@ -824,4 +826,29 @@ public class HttpClientTest extends AbstractHttpClientServerTest
                 });
         Assert.assertTrue(latch.await(10, TimeUnit.SECONDS));
     }
+
+    @Test
+    public void testCustomUserAgent() throws Exception
+    {
+        final String userAgent = "Test/1.0";
+        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);
+                ArrayList<String> userAgents = Collections.list(request.getHeaders("User-Agent"));
+                Assert.assertEquals(1, userAgents.size());
+                Assert.assertEquals(userAgent, userAgents.get(0));
+            }
+        });
+
+        ContentResponse response = client.newRequest("localhost", connector.getLocalPort())
+                .scheme(scheme)
+                .agent(userAgent)
+                .timeout(5, TimeUnit.SECONDS)
+                .send();
+
+        Assert.assertEquals(200, response.getStatus());
+    }
 }