Bug 178394 NPE in marker adapter buildAll markers
This shows up occasionally in the test suite logs. Probably happening during shutdown !STACK 0 java.lang.NullPointerException at org.eclipse.ui.views.markers.internal.MarkerAdapter.buildAllMarkers(MarkerAdapter.java:262) at org.eclipse.ui.views.markers.internal.MarkerView.updateForContentsRefresh(MarkerView.java:570) at org.eclipse.ui.views.markers.internal.MarkerView$MarkerProcessJob.run(MarkerView.java:151) at org.eclipse.core.internal.jobs.Worker.run(Worker.java:58)
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/views/markers/internal/MarkerView.java
loadFiltersPreferences();
	}
	/**
	 * Load the filters preference.
	 */
	private void loadFiltersPreferences() {
		String preference = IDEWorkbenchPlugin.getDefault()
				.getPreferenceStore().getString(getFiltersPreferenceName());
		if (preference.equals(IPreferenceStore.STRING_DEFAULT_DEFAULT)) {
			createDefaultFilter();
			return;
		}
		StringReader reader = new StringReader(preference);
		try {
			restoreFilters(XMLMemento.createReadRoot(reader));
		} catch (WorkbenchException e) {
			IDEWorkbenchPlugin.log(e.getLocalizedMessage(), e);
		}
	}
	/**
	 * Update for filter changes. Save the preference and clear the enabled
	 * cache.
	 */
	void updateForFilterChanges() {
		XMLMemento memento = XMLMemento.createWriteRoot(TAG_FILTERS_SECTION);
		writeFiltersSettings(memento);
		StringWriter writer = new StringWriter();
		try {
			memento.save(writer);
		} catch (IOException e) {