Bug 315281 update copyrights for 3.6
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/extensions/Binding.java
private final Set rootPatterns = new HashSet();
	private final Set includePatterns = new HashSet();
	private final Set excludePatterns = new HashSet();
	private final String TAG_EXTENSION;
	private final Map knownIds = new HashMap();
	private final Map knownRootIds = new HashMap();
	protected Binding(String tagExtension) {
		TAG_EXTENSION = tagExtension;
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.ui.internal.navigator.extensions.INavigatorViewerDescriptor#isVisibleExtension(java.lang.String)
	 */
	boolean isVisibleExtension(String anExtensionId) {
		
		
		if (knownIds.containsKey(anExtensionId)) {
			
			return ((Boolean) knownIds.get(anExtensionId)).booleanValue();