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
protected List approvers = new ArrayList();
	/**
	 * a map of undo limits per context
	 */
	private HashMap limits = new HashMap();
	/**
	 * the list of {@link IOperationHistoryListener}s
	 */
	protected List listeners = new ArrayList();
	/**
	 * the list of operations available for redo, LIFO
	 */
	private List redoList = new ArrayList();
	/**
	 * the list of operations available for undo, LIFO
	 */
	private List undoList = new ArrayList();
	
	/**
	 * an operation that is "absorbing" all other operations while
	 * it is open.  When this is not null, other operations added or
	 * executed are ignored and assumed to be triggered by the batching
	 * 
	 */
	private IUndoableOperation batchingOperation = null;
	
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.commands.operations.IOperationHistory#add(org.eclipse.core.commands.operations.IUndoableOperation)