Bug 218884 [DataBinding] Add API: WorkbenchObservables
... for things like listening to ISelectionService
bundles/org.eclipse.core.databinding.observable/src/org/eclipse/core/databinding/observable/Observables.java
/**
	 * Returns an observable set of the given element type, backed by the given
	 * set.
	 * 
	 * @param set
	 *            the set to wrap in an IObservableSet
	 * @param elementType
	 *            the element type of the returned set
	 * @return Returns an observable set backed by the given unchanging set
	 * @since 1.1
	 */
	public static IObservableSet staticObservableSet(Set set, Object elementType) {
		return staticObservableSet(Realm.getDefault(), set, elementType);
	}
	/**
	 * Returns an observable set belonging to the given realm, backed by the
	 * given set.
	 * 
	 * @param realm
	 *            the realm of the returned set
	 * @param set
	 *            the set to wrap in an IObservableSet
	 * @return an observable set backed by the given unchanging set
	 */
	public static IObservableSet staticObservableSet(Realm realm, Set set) {
		return staticObservableSet(realm, set, Object.class);
	}
	/**
	 * Returns an observable set of the given element type and belonging to the
	 * given realm, backed by the given set.