In some cases InspectorPageAgent::findFrameWithSecurityOrigin returns NULL even if corresponding frame exists.
White pane is displayed in Local storage URLS instead of keys & values
The issue is that document.setDomain("cnn.com") is executed against the main frame's document, whose security origin used to be "www.cnn.com". This results in a SecurityOrigin mismatch in the backend.
Created attachment 191164 [details]
Committed r144601: <http://trac.webkit.org/changeset/144601>