Bug 88838 [Undo] - API cleanup - remove IContextConsultingOperationApprover
Early on this was involved in scenarios where editors examined other operations. This is no longer used. Operation approvers generally apply to all contexts and are installed at the OperationHistory level. Until there is a concrete need for this API it should be removed. It is gratuitous at this point.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
* Notify listeners that an operation has been undone.
	 */
	protected void notifyChanged(IUndoableOperation operation) {
		if (DEBUG_OPERATION_HISTORY_NOTIFICATION) {
			System.out.print("OPERATIONHISTORY >>> OPERATION_CHANGED ");  
			System.out.print(operation);
			System.out.println();
		}
		OperationHistoryEvent event = new OperationHistoryEvent(
				OperationHistoryEvent.OPERATION_CHANGED, this, operation);
		preNotifyOperation(operation, event);
		for (int i = 0; i < listeners.size(); i++)
			try {
				((IOperationHistoryListener) listeners.get(i))
					.historyNotification(event);
			} catch (Exception e) {
				handleNotificationException(e);
			}
	}
	/*
	 * A history notification is about to be sent.  Notify the operation before hand
	 * if it implements IHistoryNotificationAwareOperation.
	 * 
	 * This method is provided for legacy undo frameworks that rely on notification
	 * from their undo managers before any listeners are notified about changes
	 * in the operation.
	 */
	private void preNotifyOperation(IUndoableOperation operation, OperationHistoryEvent event) {
		if (operation instanceof IHistoryNotificationAwareOperation) {
			try {