Bug 214137 [Markers] Unbound system filters should be bound to problems view.
In 3.3 we supported systemFilters which are not currently picked up by the problems view. We should pick these up for compatiblity.
bundles/org.eclipse.ui.ide/src/org/eclipse/ui/internal/views/markers/CachedMarkerBuilder.java
*/
	private void loadFiltersPreference() {
		loadFiltersFrom(IDEWorkbenchPlugin.getDefault().getPreferenceStore()
				.getString(getMementoPreferenceName()));
		String legacyFilters = getLegacyFiltersPreferenceName();
		String migrationPreference = legacyFilters
				+ MarkerSupportInternalUtilities.MIGRATE_PREFERENCE_CONSTANT;
		if (IDEWorkbenchPlugin.getDefault().getPreferenceStore().getBoolean(
				migrationPreference))
			return;
		
		loadLegacyFiltersFrom(IDEWorkbenchPlugin.getDefault()
				.getPreferenceStore().getString(legacyFilters));
		
		IDEWorkbenchPlugin.getDefault().getPreferenceStore().setValue(
				migrationPreference, true);
	}
	/**
	 * Load the pre-3.4 filters.
	 * 
	 * @param mementoString
	 */
	private void loadLegacyFiltersFrom(String mementoString) {
		if (mementoString.equals(IPreferenceStore.STRING_DEFAULT_DEFAULT))
			return;
		IMemento memento;
		try {
			memento = XMLMemento
					.createReadRoot(new StringReader(mementoString));
			restoreLegacyFilters(memento);