Bug 126658 [CommonNavigator] [DND] Complete definition of DND API
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/NavigatorContentService.java
return rootContentProviders;
	}
	/**
	 * 
	 * Return all of the label providers that are enabled for the given element.
	 * A label provider is 'enabled' if its corresponding content provider
	 * returned the element, or the element is described in the content
	 * extension's <b>triggerPoints</b> expression.
	 * 
	 * @param anElement
	 *            An element from the tree (any element contributed to the
	 *            tree).
	 * @return The set of label providers that may be able to provide a valid
	 *         (non-null) label.
	 */
	public ILabelProvider[] findRelevantLabelProviders(Object anElement) {
		return extractLabelProviders(findContentExtensionsWithPossibleChild(
				anElement, false));
	}
	/**
	 * Search for extensions that declare the given element in their
	 * <b>triggerPoints</b> expression.
	 * 
	 * @param anElement
	 *            The element to use in the query
	 * @return The set of {@link INavigatorContentExtension}s that are
	 *         <i>visible</i> and <i>active</i> for this content service and
	 *         either declared through a
	 *         <b>org.eclipse.ui.navigator.viewer/viewerContentBinding</b> to
	 *         be a root element or have a <b>triggerPoints</b> expression that