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
* method.
	 * </p>
	 * 
	 * @see org.eclipse.ui.part.ViewPart#saveState(org.eclipse.ui.IMemento)
	 */
	public void saveState(IMemento aMemento) {
		aMemento.putInteger(LINKING_ENABLED, (isLinkingEnabled) ? 1 : 0);
		super.saveState(aMemento);
		commonManager.saveState(aMemento);
		commonViewer.getNavigatorContentService().saveState(aMemento);
	}
	/**
	 * <p>
	 * Force the workbench to focus on the Common Navigator tree.
	 * </p>
	 * 
	 * @see org.eclipse.ui.part.WorkbenchPart#setFocus()
	 */
	public void setFocus() {
		if (commonViewer != null) {
			commonViewer.getTree().setFocus();
		}
	}
	/**
	 * <p>
	 * Set the selection to the Common Navigator tree, and expand nodes if
	 * necessary. Use caution when invoking this method as it can cause
	 * Navigator Content Extensions to load, thus causing plugin activation.
	 * </p>
	 *