Bug 89031 [Undo/Redo] IWorkbench#getOperationSupport() marked experimental
IWorkbench#getOperationSupport() marked experimental
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/IOperationHistory.java
*            <code>true</code> if the operation successfully completed.
	 *            Listeners should be notified with <code>DONE</code>,
	 *            <code>UNDONE</code>, or <code>REDONE</code>.
	 *            <code>false</code> if the operation did not successfully
	 *            complete. Listeners should be notified with
	 *            <code>OPERATION_NOT_OK</code>.
	 * @param addToHistory -
	 *            <code>true</code> if the operation should be added to the
	 *            history, <code>false</code> if it should not. If the
	 *            <code>operationOK</code> parameter is <code>false</code>,
	 *            the operation will never be added to the history.
	 * @param mode -
	 *            the mode the operation was opened in. Can be one of
	 *            <code>EXECUTE</code>, <code>UNDO</code>, or
	 *            <code>REDO</code>.  This determines what notifications are
	 *            sent.
	 */
	void closeOperation(boolean operationOK, boolean addToHistory, int mode);
	/**
	 * Return whether there is a redoable operation available in the given
	 * context.
	 * 
	 * @param context -
	 *            the context to be checked
	 * @return <code>true</code> if there is a redoable operation,
	 *         <code>false</code> otherwise.
	 */
	boolean canRedo(IUndoContext context);
	/**
	 * Return whether there is an undoable operation available in the given