Bug 189490 [CommonNavigator] Go To->Resource won't enable
I0524 1. Open the Project Explorer in the Resource perspective 2. Create a vanilla project P 3. Create a folder F 4. Create a file resource R Open the Navigate->Go To file. "Resource..." will remain disabled.
bundles/org.eclipse.ui.navigator/src/org/eclipse/ui/navigator/CommonViewer.java
protected void handleDispose(DisposeEvent event) {
		dispose();
		super.handleDispose(event);
	}
 
	/**
	 * <p>
	 * Disposes of the NavigatorContentService, which will dispose the Content
	 * and Label providers.
	 * </p>
	 */
	public void dispose() {
		if (contentService != null) {
			contentService.dispose();
		}
		clearSelectionCache();
	}
	/**
	 * Sets this viewer's sorter and triggers refiltering and resorting of this
	 * viewer's element. Passing <code>null</code> turns sorting off.
	 * 
	 * @param sorter
	 *            a viewer sorter, or <code>null</code> if none
	 */
	public void setSorter(ViewerSorter sorter) {
		if (sorter != null && sorter instanceof CommonViewerSorter) {
			((CommonViewerSorter) sorter).setContentService(contentService);
		}
		super.setSorter(sorter);
	}