Bug 179551 [Undo] DefaultOperationHistory should write exceptions to log when running in Eclipse
I20070323-1616 DefaultOperationHistory#handleNotificationException(..) should write exceptions to the log when running in Eclipse. Bugs like 176644 are easy to miss when exceptions only appear on the console.
bundles/org.eclipse.core.commands/src/org/eclipse/core/commands/operations/DefaultOperationHistory.java
*/
	public static boolean DEBUG_OPERATION_HISTORY_UNEXPECTED = false;
	/**
	 * This flag can be set to <code>true</code> if the history should print
	 * information to <code>System.out</code> whenever an undo context is
	 * disposed. This flag should be used for debug purposes only.
	 */
	public static boolean DEBUG_OPERATION_HISTORY_DISPOSE = false;
	/**
	 * This flag can be set to <code>true</code> if the history should print
	 * information to <code>System.out</code> during the open/close sequence.
	 * This flag should be used for debug purposes only.
	 */
	public static boolean DEBUG_OPERATION_HISTORY_OPENOPERATION = false;
	/**
	 * This flag can be set to <code>true</code> if the history should print
	 * information to <code>System.out</code> whenever an operation is not
	 * approved. This flag should be used for debug purposes only.
	 */
	public static boolean DEBUG_OPERATION_HISTORY_APPROVAL = false;
	static final int DEFAULT_LIMIT = 20;
	/**
	 * the list of {@link IOperationApprover}s
	 */
	ListenerList approvers = new ListenerList(ListenerList.IDENTITY);
	/**
	 * a map of undo limits per context
	 */
	private Map limits = Collections.synchronizedMap(new HashMap());
	/**