Point of note, we check two different things:
1) Is UseKohaPlugins enabled
2) Is enabled_plugins set in the Koha config file

I think we should have a method in Koha::Plugins that checks both and returns true/false. If there are any parts of Koha that only check one for a good reason, we can have another method to check just that.

(In reply to Kyle M Hall from comment #1)
> Point of note, we check two different things:
> 1) Is UseKohaPlugins enabled
> 2) Is enabled_plugins set in the Koha config file
> 
> I think we should have a method in Koha::Plugins that checks both and
> returns true/false. If there are any parts of Koha that only check one for a
> good reason, we can have another method to check just that.

Or you could return a hashref.
Configured => true/false                    # true when both syspref and config
Failures => [systempreference,config,other] # an array with what fails

Then:
my $rv = Koha::Plugins->configured();
if ( $rv->{Configured} ) { ... }
or perhaps
if ( $rv->{Configured} || ! grep { $_ eq 'systempreference' } @{$rv->Failures} ) {
 ...
}