Fix version_negotiation_test timing out.

sdk/lib/_internal/pub/test/hosted/version_negotiation_test.dart

Index: sdk/lib/_internal/pub/test/hosted/version_negotiation_test.dart
diff --git a/sdk/lib/_internal/pub/test/hosted/version_negotiation_test.dart b/sdk/lib/_internal/pub/test/hosted/version_negotiation_test.dart
index 64247ea1b453a9d6d05b2a1c995750a03303b7e5..5117afe627e99dff779c7688419d325dbc8c186f 100644
--- a/sdk/lib/_internal/pub/test/hosted/version_negotiation_test.dart
+++ b/sdk/lib/_internal/pub/test/hosted/version_negotiation_test.dart
@@ -54,12 +54,6 @@ main() {
         request.response.close();
       });
 
-      // TODO(nweiz): this shouldn't request the versions twice (issue 11077).

[Anders Johnsen, 2014/01/05 20:47:00]

How is removing this test fixing the issue? :)

[Bob Nystrom, 2014/01/06 18:56:23]

This isn't removing the test. :)

What this test does is spin up a test server, and then it runs pub. Pub should
hit that server, and then this test evaluates what pub outputs.

Previously, pub was sending two HTTP requests to that server. It never should
have. I fixed the code in the version solver that led to that, so now I can
remove it here.

As a nice side effect, this test is now a bit faster since pub is doing less
networking. I'm *hoping* this means it won't time out anymore, but we'll have to
see how it goes on the bots.

[Anders Johnsen, 2014/01/07 05:59:29]

Ahh, I see - great then ;)

-      server.handle('GET', '/api/packages/foo', (request) {
-        request.response.statusCode = 406;
-        request.response.close();
-      });
-
       pub.shouldExit(1);
 
       expect(pub.remainingStderr(), completion(equals(