Bug 228760 [Markers] Column orientation not stored when markers views are closed
If we re-order view columns by drag and drop or add/remove them using the preferences the values we ended up with are not restored on restart.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/CachedMarkerBuilder.java
*/
	boolean hasNoMarkers() {
		return currentMap == null;
	}
	/**
	 * Initialise the visible fields based on the initial settings.
	 */
	private void initialiseVisibleFields() {
		MarkerField[] initialFields = getGenerator().getInitialVisible();
		visibleFields = new MarkerField[initialFields.length];
		System.arraycopy(initialFields, 0, visibleFields, 0,
				initialFields.length);
	}
	/**
	 * Create a preference listener for any preference updates.
	 */
	private void initializePreferenceListener() {
		preferenceListener = new IPropertyChangeListener() {
			/*
			 * (non-Javadoc)
			 * 
			 * @see org.eclipse.jface.util.IPropertyChangeListener#propertyChange(org.eclipse.jface.util.PropertyChangeEvent)
			 */
			public void propertyChange(PropertyChangeEvent event) {
				if (event.getProperty().equals(getMementoPreferenceName())) {
					rebuildFilters();
				}
			}
		};
		IDEWorkbenchPlugin.getDefault().getPreferenceStore()