In slice_names():
In slice_names():

When we get all slices that has genes on them, and we find a slice that
is not a reference slice, make sure that we only fetch the unique region
of it.  This solves the problem of genes getting new stable IDs even
though they haven't changed.

muffato/ensembl,muffato/ensembl,Ensembl/ensembl,at7/ensembl,james-monkeyshines/ensembl,james-monkeyshines/ensembl,willmclaren/ensembl,at7/ensembl,muffato/ensembl,danstaines/ensembl,Ensembl/ensembl,mjg17/ensembl,danstaines/ensembl,james-monkeyshines/ensembl,Ensembl/ensembl,mjg17/ensembl,willmclaren/ensembl,at7/ensembl,james-monkeyshines/ensembl,muffato/ensembl,mjg17/ensembl,Ensembl/ensembl,danstaines/ensembl,mjg17/ensembl,at7/ensembl