Show local data and SQL tab if Firefox is offline

[ghost]

We currently show an error like Failed to load collection: [Exception... "NS_ERROR_UNKNOWN_HOST" nsresult: "0x804b001e (NS_ERROR_UNKNOWN_HOST)" location: "JS frame :: resource://services-sync/resource.js :: Channel_onStopRequest :: line 422" data: no] underneath "Collections" if the Sync server is unreachable.

I wonder if we could at least show local records, and the SQL query UI for bookmarks. That would be handy for hacking on the train. 🏠🚆🏢

[mhammond]

We should do this but it's not really trivial, as when info/collections fails we don't even know what collections exist - ie, this would require a fairly large restructure...