Fix server/ui/V4Pages test

[thopre]

Summary

Commit cc9b7c48f8e22c1b883950ef214bb710c85ca412 changed redirect URL to
be relative. However, it did not update the corresponding redirect tests
due to them passing because of the cPerf issue fixed in
f98bc1b3018248fbe551b0e7491ac5ba388216d5. These tests are now failing.
This commit fixes them.

[cmatthews]

LGTM

[thopre]

Landed as 52ea66719d01d3d18651946c1b83790ca371d34c

tests/server/ui/V4Pages.py

def main():
     # Don't crash when requesting non-existing data
     check_code(client, '/v4/compile/machine/9999',
                expected_code=HTTP_NOT_FOUND)
     check_code(client, '/v4/compile/machine/-1', expected_code=HTTP_NOT_FOUND)
     check_code(client, '/v4/compile/machine/a', expected_code=HTTP_NOT_FOUND)
 
     # Check the compare machine form gives correct redirects.
     resp = check_code(client, '/v4/nts/machine/2/compare?compare_to_id=3', expected_code=HTTP_REDIRECT)
-    assert resp.headers['Location'] == "http://localhost/db_default/v4/nts/9?compare_to=4"
+    assert resp.headers['Location'] == "/db_default/v4/nts/9?compare_to=4"
     resp = check_code(client, '/v4/nts/machine/3/compare?compare_to_id=2', expected_code=HTTP_REDIRECT)
-    assert resp.headers['Location'] == "http://localhost/db_default/v4/nts/4?compare_to=9"
+    assert resp.headers['Location'] == "/db_default/v4/nts/4?compare_to=9"
 
     # Get the order summary page.
     check_html(client, '/v4/compile/all_orders')
 
     # Get an order page.
     check_html(client, '/v4/compile/order/3')
 
     # Get a run result page (and associated views).
def main():
     assert resp.get_data(as_text=True) == "Ok"
     resp = check_code(client, '/ping')
     assert resp.get_data(as_text=True) == "pong"
 
     # Check we can convert a sample into a graph page.
     graph_to_sample = check_code(client, '/db_default/v4/nts/graph_for_sample/10/compile_time?foo=bar',
                                  expected_code=HTTP_REDIRECT)
     assert graph_to_sample.headers['Location'] in (
-            "http://localhost/db_default/v4/nts/graph?foo=bar&plot.0=2.6.0",
-            "http://localhost/db_default/v4/nts/graph?plot.0=2.6.0&foo=bar")
+            "/db_default/v4/nts/graph?foo=bar&plot.0=2.6.0",
+            "/db_default/v4/nts/graph?plot.0=2.6.0&foo=bar")
 
     # Check that is we ask for a sample or invalid field, we explode with 400s.
     check_code(client, '/db_default/v4/nts/graph_for_sample/10000/compile_time?foo=bar',
                expected_code=HTTP_NOT_FOUND)
     check_code(client, '/db_default/v4/nts/graph_for_sample/10/not_a_metric?foo=bar',
                expected_code=HTTP_BAD_REQUEST)
 
     # check get_geomean_comparison_result with empty unchanged_tests
     check_html(client, '/v4/nts/11')
     check_html(client, '/v4/nts/12')
 
 
 if __name__ == '__main__':
     main()