MIM Adapter Error if no IDB Adapters Enabled

Tested Against: Identity Broker v5.3

Currently if you have no adapters enabled in IDB, and you attempt to create an MA in MIM using the MIM Adapter ECMA2, you get the following error:

The extensible extension returned an unsupported error.
  
The stack trace is:
 "System.InvalidOperationException: Sequence contains no elements
   at System.Linq.Enumerable.Aggregate[TSource](IEnumerable`1 source, Func`3 func)
   at Unify.Product.IdentityBroker.LdapConnectionProxy.get_Schema()
   at Unify.Product.IdentityBroker.UnifyLdapConnectorTypeProxy.GetSchema(KeyedCollection`2 configParameters)
Forefront Identity Manager 4.4.1302.0"

It would be good if the error could either be reported in a more logical way (IE inform that there's no adapters enabled, and therefore no OU's to load), or simply allow the creation process to continue and the user will realise there's no adapters enabled in a subsequent step.

The error also occurs if you have adapters which are enabled with valid schema, but inhibited due to a condition with the base connector.