Bug 89031 [Undo/Redo] IWorkbench#getOperationSupport() marked experimental
IWorkbench#getOperationSupport() marked experimental
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/OperationHistoryEvent.java
* 
	 * If the operation successfully executes, clients will also receive a
	 * notification that it has been added to the history.
	 */
	public static final int ABOUT_TO_EXECUTE = 0x0001;
	/**
	 * ABOUT_TO_REDO indicates that an operation is about to be redone.
	 * Listeners should prepare for the redo as appropriate. Listeners will
	 * receive a redone notification if the operation is successful, or an
	 * operationNotCompleted notification if the redo is cancelled or otherwise
	 * fails.
	 */
	public static final int ABOUT_TO_REDO = 0x0002;
	/**
	 * ABOUT_TO_UNDO indicates that an operation is about to be undone.
	 * Listeners should prepare for the undo as appropriate. Listeners will
	 * receive an undone notification if the operation is successful, or an
	 * operationNotCompleted notification if the undo is cancelled or otherwise
	 * fails.
	 */
	public static final int ABOUT_TO_UNDO = 0x0004;
	/**
	 * DONE indicates that operation has been executed. Listeners can take
	 * appropriate action, such as revealing any relevant state in the UI. This
	 * notification is only received for those operations executed by the
	 * operation history. Operations that are added to the history after
	 * execution do not trigger this notification.
	 * 
	 * Clients will also receive a notification that the operation has been
	 * added to the history.