...from webdav Content::getResourceType, as otherwise Content::abort would be
blocked waiting for the mutex (in code that would call abort, which will be
required to fix rhbz#915743 "thread deadlock/slow join in insert->hyperlink in
impress").  This required to get the odd reference to enum return type of
getResourceType straight.

Also, propagate information about !shouldAccessNetworkAfterException from
getResourceType out to getPropertyValues, to avoid further calls that would
again block/fail.

Change-Id: I8b9d43a61eb4078acb90079c4eb7aa98a59a8983