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/IOperationHistory.java
*         operation available. There is no guarantee that the returned
	 *         operation is valid for redo.
	 */
	IUndoableOperation getRedoOperation(IUndoContext context);
	/**
	 * Get the array of operations that can be undone in the specified context.
	 * The operations are in the order that they would be undone if successive
	 * "Undo" commands were invoked.
	 * 
	 * @param context -
	 *            the context for the undo
	 * @return the array of operations in the history
	 */
	IUndoableOperation[] getUndoHistory(IUndoContext context);
	/**
	 * <p>
	 * Open this operation and consider it the primary operation in a batch of
	 * related operations. Consider all operations that are subsequently
	 * executed (or added) to be part of this operation and assign the
	 * context(s) of subsequent operations to this operation. When an operation
	 * is opened, listeners will immediately receive an
	 * <code>ABOUT_TO_EXECUTE</code>) notification for the operation.
	 * Notifications for execution or adding subsequent operations will not be
	 * sent as long as this operation is open.
	 * 
	 * <p>
	 * Note: This method is intended to be used by legacy undo frameworks that
	 * do not expect related undo operations to appear in the same undo stack as
	 * the triggering undo operation. When an operation is open, any subsequent
	 * operations added or executed are assumed to be triggered by model change