Bug 130182 [CommonNavigator][Help] missing help in Customize View dialog
open the Filters... dialog and click the help button, note no help appears.
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/navigator/INavigatorViewerDescriptor.java
*         the default set (as defined by {@link NavigatorActionService})
	 *         should be used. An empty list indicates there are no declarative
	 *         insertion points.
	 */
	MenuInsertionPoint[] getCustomInsertionPoints();
	/**
	 * @param aPropertyName
	 *            A property name corresponding to a configuration option from
	 *            <b>org.eclipse.ui.navigator.viewer</b>
	 * @return The unmodified string value returned from the extension (<b>null</b>
	 *         is a possible return value).
	 */
	String getStringConfigProperty(String aPropertyName);
	/**
	 * @param aPropertyName
	 *            A property name corresponding to a configuration option from
	 *            <b>org.eclipse.ui.navigator.viewer</b>
	 * @return The boolean value returned from the extension (<b>null</b> is a
	 *         possible return value).
	 */
	boolean getBooleanConfigProperty(String aPropertyName);
	
	/**
	 * @return the help context associated with this viewer as specified by 
	 * the helpContext attribute of the &lt;viewer /&gt; element in the
	 * <b>org.eclipse.ui.navigator.viewer</b> extension point.
	 * @since 3.4
	 */
	String getHelpContext();
}