Chrome's extension update method can host multiple versions side-by-side for some period of time.  e.g.
~/Extensions/
`-- alksdjflkasjdfkaljsfd/  # extension id
    |-- 0.5.1.3_0/
    `-- 0.5.1.4_0/

so when we go searching for containers by name, we might hit the old one first until Chrome expires things.

we can change things so we walk the entire tree every time and use the latest version (using base::Version to compare extension version or the imageloader version), or we could do it by timestamp ...