It took me a while to figure out how to do this:

var objectContext = ((IObjectContextAdapter)dbContext).ObjectContext;
var refreshableObjects = objectContext.ObjectStateManager
.GetObjectStateEntries(EntityState.Added | EntityState.Deleted | EntityState.Modified | EntityState.Unchanged)
.Where(x => entityType == null || x.Entity.GetType() == entityType)
.Where(entry => entry.EntityKey != null)
.Select(e => e.Entity)
.ToArray();
objectContext.Refresh(RefreshMode.StoreWins, refreshableObjects);