Bug 256516 [TabbedProperties] TabbedPropertySheetPage to allow some options
bundles/org.eclipse.ui.views.properties.tabbed/src/org/eclipse/ui/views/properties/tabbed/TabbedPropertySheetPage.java
protected IStructuredContentProvider getTabListContentProvider() {
		return registry.getTabListContentProvider();
	}
	/**
	 * Dispose the contributor with the provided contributor id. This happens on
	 * part close as well as when contributors switch between the workbench
	 * part and contributor from a selection.
	 */
	private void disposeContributor() {
		/**
		 * If the current tab is about to be disposed we have to call
		 * aboutToBeHidden
		 */
		if (currentTab != null) {
			currentTab.aboutToBeHidden();
			currentTab = null;
		}
		disposeTabs(descriptorToTab.values());
		descriptorToTab = new HashMap();
		/**
		 * Remove the label provider change listener.
		 */
		if (hasTitleBar && registry != null) {
			registry.getLabelProvider().removeListener(this);
		}
		if (selectionContributor != null) {
			/**
			 * remove the selection contributed registry.
			 */
			TabbedPropertyRegistryFactory.getInstance().disposeRegistry(