Bug 156865 Undo / Redo marker actions not updated
I20060906-1200 If a file gets delete after adding/changing/removing a marker then the Undo and Redo actions are not updated and still show, e.g. Undo Add Task Redo Add Task Executing the undo or redo does nothing (no feedback, no .log entry) and the undo and redo menu text remains the same and enabled.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/ide/undo/AbstractMarkersOperation.java
if (attributes == null || markers == null
				|| attributes.length != markers.length || markers.length == 0) {
			monitor.worked(work);
			return;
		}
		int markerWork = work / markers.length;
		for (int i = 0; i < markers.length; i++) {
			if (mergeAttributes) {
				Map oldAttributes = markers[i].getAttributes();
				int increment = markerWork / attributes[i].size();
				Map replacedAttributes = new HashMap();
				for (Iterator iter = attributes[i].keySet().iterator(); iter
						.hasNext();) {
					String key = (String) iter.next();
					Object val = attributes[i].get(key);
					markers[i].setAttribute(key, val);
					replacedAttributes.put(key, oldAttributes.get(key));
					monitor.worked(increment);
				}
				attributes[i] = replacedAttributes;
			} else {
				
				Map oldAttributes = markers[i].getAttributes();
				markers[i].setAttributes(attributes[i]);
				attributes[i] = oldAttributes;
			}
		}
	}
	/*
	 * Set the marker descriptions that describe markers that can be created.