Resource revision fails to request content if it was not yet loaded for resource. Test scenario: Open inspector, open elements panel, open any site with css, change css values in the side panel (enough to trigger revision creation). Open resources panel, and open revision created without first opening original resource. This way ResourceRevision.requestContent(callback) method will be called.
Created attachment 99092 [details] Patch
Comment on attachment 99092 [details] Patch Clearing flags on attachment: 99092 Committed r90022: <http://trac.webkit.org/changeset/90022>
All reviewed patches have been landed. Closing bug.