In working on bug 29483 it was found that the logic of CanBookBeRenewed can be flawed when relating to AllowRenewalIfOtherItemsAvailable

At checkin we call 'CheckReserves' to find holds on the current item and will fill only holds that obey hold 'policies' - but we will also fill a hold that violates the 'rules'

To recreate:
1 - Set circ rules to allow 5 holds for All/All
2 - Set an itemtype level circ rule to allow 0 holds
3 - Place a title level hold on a record with an item of that type and one of another type
4 - Note while placing hold that you cannot select the item of that type
5 - Check in the item with that type - the hold is trapped - ignore it for now
6 - Check out the other item to a patron
7 - Note the renew column in checkouts says 'On hold'
8 - Set AllowRenewalIfOtherItemsAvailable to 'Allow'
9 - Note the renew column still says 'On hold' despite the fact that that item will fill the existing hold