[Catalyst] Catalyst::Action::SerializeBase::_load_content_plugins default behavior

[Tomas Doran]

Dave Goehrig wrote:
> Based on the documentation, both behaviors are correct, but it seems to
> me that if I specify a local mapping that it should override the default
> map as it did in the old behavior.  Was this change a bug or a design
> decision?

Bug.

If you could provide a failing test case that'd be most appreicated.

Cheers
t0m