Bug 198971 [CommonNavigator] Provide extension schema for setting help ID
I haven't been able to find a way to set the help ID for a view using the common resource navigator. It seems that having schema support for this would be the best way to handle this.
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/navigator/INavigatorViewerDescriptor.java
* 
	 * Custom insertion points are declared through a nested 'popupMenu' element
	 * in the <b>org.eclipse.ui.navigator.viewer</b> extension point. Each
	 * insertion point represents either a {@link Separator} or
	 * {@link GroupMarker} in the context menu of the viewer.
	 * <p>
	 * 
	 * @return The set of custom insertion points, if any. A null list indicates
	 *         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);
}