Load the URL for the bug and you will see Local Storage and Session Storage show up twice for the same origin (http://www.npr.org/). It should only show up once or the origin string is wrong and once is https or a different port?
The security origin is different per following check in SecurityOrigin::equal. if (m_domainWasSetInDOM != other->m_domainWasSetInDOM) return false; Apparently this happens when script does document.domain = "foo".
This is probably duplicate of https://bugs.webkit.org/show_bug.cgi?id=99266.
Closing as invalid, as this bug pertains to the old inspector UI and/or its tests. Please file a new bug (https://www.webkit.org/new-inspector-bug) if the bug/feature/issue is still relevant to WebKit trunk.