Bug 302791 [CommonNavigator] Associated editor does not close when deleting resource (editorInput) through CommonNavigator
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/actions/CommonActionProviderDescriptor.java
provider = SkeletonActionProvider.INSTANCE;
		}
		return provider;
	}
	/**
	 * Determine if this action provider descriptor is enabled for the given selection.
	 * The action provider descriptor is enabled for the selection if and only if it is
	 * enabled for each element in the selection.
	 * 
	 * @param aStructuredSelection
	 *            The selection from the viewer
	 * @return True if and only if the extension is enabled for each element in
	 *         the selection.
	 */
	public boolean isEnabledFor(IStructuredSelection aStructuredSelection) {
		if (enablement == null) {
			return false;
		}
		
		if(aStructuredSelection.isEmpty()) {
			IEvaluationContext context = null; 
			context = NavigatorPlugin.getEmptyEvalContext();
			try { 
				if (enablement.evaluate(context) != EvaluationResult.TRUE) {
					return false;
				}
			} catch (CoreException e) {
				NavigatorPlugin.log(IStatus.ERROR, 0, e.getMessage(), e);
				return false;
			}