def prepare_relation(name, options)
      PublicActivity.resolve_value(self,
        (options.has_key?(name) ? options[name] : (
          self.send("activity_#{name}") || self.class.send("activity_#{name}_global")
          )
        )
      )
    end
def prepare_relation(name, options)
      PublicActivity.resolve_value(self,
        (options.has_key?(name) ? options[name] : (
          self.send("activity_#{name}") || self.class.send("activity_#{name}_global")
          )
        )
      )
    end
Prepares relation to be saved
 to Activity. Can be :recipient or :owner
 @private