Rename the WP_HTTP testcase 'test_location_header_on_200' to 'test_location_header_on_201' and modify test / test script accordingly, PHP doesn't allow us to issue a Location with a 200 response, and the ticket it refers to is specifically about 201 responses.
See #16889


git-svn-id: https://unit-tests.svn.wordpress.org/trunk@1231 4a5a2adb-35eb-4268-9a1b-fe04a4134342