GURL::inner_url() is nominally the nested URL in file system URLs.  However, GURL::inner_url()::spec() returns the same value of GURL::spec(), which is confusing and incorrect.  inner_url() seems to mostly exist so its PathForRequest() method can be called, which apparently behaves as it should, but the value returned by inner_url()::spec() should be fixed so that it makes sense.

Another option would be to get rid of inner_url(), at least as a public method, and make special accessors for the parts of filesystem URLs we actually care about.