This is used to encapsulate an IItemPropertySource along with the object for which it is an item property source
and make it behave like an IPropertySource.
This populates the specified manager with ActionContributionItems
based on the IActions contained in the actions collection,
by inserting them before the specified contribution item contributionID.
port() -
Method in class org.eclipse.emf.common.util.URI
If this is a hierarchical URI with an authority component that has a
port portion, returns it; null otherwise.
Returns false if any command on the list returns false for Command.canExecute(),
or if some command before the last one can't be undone and hence we can't test all the commands for executability.