Bug 143430 [CommonNavigator] CommonNavigator requires initialInput to be Adaptable
I have a root nodes that is not Adaptable and that does not fit well with CommonNavigator.getInitialInput which requires (for no real good reason ?) to be Adaptable. Should this not just be an Object ?
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/navigator/CommonNavigator.java
.getSaveablesService().init(this, getCommonViewer(),
						saveablesLifecycleListener);
		
		commonViewer.addSelectionChangedListener(new ISelectionChangedListener() {
			public void selectionChanged(SelectionChangedEvent event) {
				firePropertyChange(PROP_DIRTY);
			}});
		
		PlatformUI.getWorkbench().getHelpSystem().setHelp(commonViewer.getControl(),  HELP_CONTEXT);
		
		stats.endRun();
	}
	/**
	 * <p>
	 * Updates the title text and title tool tip. Called whenever the input of
	 * the viewer changes.
	 * </p>
	 * @since 3.4
	 */
	public void updateTitle() {
		Object input = commonViewer.getInput();
		if (input == null) {
			setTitleToolTip(""); 
		} else {
			String inputToolTip = getFrameToolTipText(input);
			setTitleToolTip(inputToolTip);
		}
	}
	
	/**