Create an set-up method for 
IN_PROC_BROWSER_TEST_P: HTTPAuthEmptyRealmAfterHTMLBlacklisted,
HTMLLoginAfterHTTPAuthIsBlacklisted, CorrectEntryForHttpAuth, BasicAuthSeparateRealms, NoLastLoadGoodLastLoad.

These methods uses almost the same test initialization.
A function that to this can be written to remove the duplicate code.