Bug 27764 IResource.findMarkers is called too often
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
if (fViewer == null)
			return super.getTitleToolTip();
		return getToolTipText(fViewer.getInput());
	}
	
	/**
	 * @see IWorkbenchPart#setFocus()
	 */
	public void setFocus() {
		fViewer.getTree().setFocus();
	}
	/**
	 * Returns the shell to use for opening dialogs.
	 * Used in this class, and in the actions.
	 */
	private Shell getShell() {
		return fViewer.getTree().getShell();
	}
	/**
	 * Returns the selection provider.
	 */
	private ISelectionProvider getSelectionProvider() {
		return fViewer;
	}
	
	/**
	 * Returns the current selection.
	 */
	private ISelection getSelection() {
		return fViewer.getSelection();