Bug 89031 [Undo/Redo] IWorkbench#getOperationSupport() marked experimental
IWorkbench#getOperationSupport() marked experimental
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/IUndoableOperation.java
* Returns whether the operation can be executed in its current state.
	 * 
	 * <p>
	 * Note: This method may be used to enable UI commands, so the computation
	 * must be fast. If necessary, this method can be optimistic in its
	 * computation and return an error status during actual execution if it is
	 * determined later that the operation cannot actually execute.
	 * 
	 * @return <code>true</code> if the operation can be executed;
	 *         <code>false</code> otherwise.
	 */
	boolean canExecute();
	/**
	 * <p>
	 * Returns whether the operation can be redone in its current state.
	 * 
	 * <p>
	 * Note: This method may be used to enable UI commands, so the computation
	 * must be fast. If necessary, this method can be optimistic in its
	 * computation and return an error status during the actual redo if it is
	 * determined later that the operation cannot actually redo.
	 * 
	 * @return <code>true</code> if the operation can be redone;
	 *         <code>false</code> otherwise.
	 */
	boolean canRedo();
	/**
	 * <p>
	 * Returns whether the operation can be undone in its current state.
	 *