Bug 305703 [Viewers][CommonNavigator] remembered contributions can leak when using filters
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/internal/navigator/extensions/StructuredViewerManager.java
synchronized (viewerDataMap) {
			if (Policy.DEBUG_VIEWER_MAP)
				System.out.println("viewer map RESET"); 
			viewerDataMap.clear();
		}
	}
	/**
	 * 
	 * @param aViewer
	 * @param contentService 
	 */
	public StructuredViewerManager(StructuredViewer aViewer, NavigatorContentService contentService) {
		super();
		viewer = aViewer;
		viewerDataMap = new HashMap();
		StructuredViewerAccess.hookAssociateListener(viewer, viewerDataMap, contentService);
	}
	/**
	 * 
	 * @return The real viewer.
	 */
	public Viewer getViewer() {
		return viewer;
	}
	/**
	 * 
	 * @param anOldInput
	 * @param aNewInput
	 */
	public void inputChanged(Object anOldInput, Object aNewInput) {