Bug 94459 [Undo] - should refactoring undo work when text undo limit is 0?
Refactoring undos are not showing up in the package explorer undo menu when the text undo limit is set to 0. Technically the refactoring operation should be permitted on the workspace undo context history. The history should just be removing the text context from the operation. One could argue this is a correctly working "feature" but need to check why it's happening and resolve the behavior as a bug or document as expected outcome.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
* list.
	 * </p>
	 * <p>
	 * Operation approvers must be prepared to receive these the operation
	 * approval messages from a background thread. Any UI access occurring
	 * inside the implementation must be properly synchronized using the
	 * techniques specified by the client's widget library.
	 * </p>
	 * 
	 * @param approver
	 *            the IOperationApprover to be added as an approver.
	 * 
	 */
	public void addOperationApprover(IOperationApprover approver) {
		approvers.add(approver);
	}
	/**
	 * <p>
	 * Add the specified listener to the list of operation history listeners
	 * that are notified about changes in the history or operations that are
	 * executed, undone, or redone. This method has no effect if the instance
	 * being added is already in the list.
	 * </p>
	 * <p>
	 * Operation history listeners must be prepared to receive notifications
	 * from a background thread. Any UI access occurring inside the
	 * implementation must be properly synchronized using the techniques
	 * specified by the client's widget library.
	 * </p>
	 *