See the discussion in http://bugs.webkit.org/show_bug.cgi?id=35180 for a bit of background.
Created attachment 49518 [details] Patch
The bug tests whether or not setting a hash fragment on an "about:blank" URL is preserved. There has been some dispute in the past over whether or not we think it should be but current interpretation of <a href="http://www.ietf.org/rfc/rfc3986.txt">RFC 3986</a> is that hash fragments should be honored for all URL types by the browser (even though their interpretation is type-specific). Note that Chromium and FF currently do not preserve this, but WebKit does.
Comment on attachment 49518 [details] Patch OK. Instead of mentioning the current behavior of Safari and Chrome in your test, I would simply state what the test does. Since eventually all browsers will pass that test. You used 2-space indent in your JS. Fix those nits and land away! :)
patch landed as r55265. closing bug.