Bug 123316 [Undo] - API BEHAVIOR - should always place a successfully undone/redone op on the redo/undo history
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/IOperationHistory.java
/**
	 * <p>
	 * Return the limit on the undo and redo history for a particular context.
	 * </p>
	 * 
	 * @param context
	 *            the context whose limit is requested
	 * 
	 * @return the undo and redo history limit for the specified context.
	 */
	int getLimit(IUndoContext context);
	/**
	 * <p>
	 * Get the array of operations in the redo history for a the specified undo
	 * context. The operations are in the order that they were added to the
	 * history, with the most recently undone operation appearing last in the
	 * array. This history is used LIFO (last in, first out) when successive
	 * "Redo" commands are invoked.
	 * 
	 * </p>
	 * 
	 * @param context
	 *            the context for the redo
	 * @return the array of operations in the history
	 */
	IUndoableOperation[] getRedoHistory(IUndoContext context);
	/**
	 * <p>
	 * Get the operation that will next be redone in the given undo context.
	 * </p>