Bug 32656 Open/Close project in package explorer looses selection on java-projects. [package explorer]
Not on non-java projects, which looks wrong when multiple java- and non-java-projects are opened/closed.
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
* 
	 * @param memento	the memento to save the state into or
	 * 					<code>null</code> to store the state in the preferences
	 * @since 2.1
	 */
	private void saveLayoutState(IMemento memento) {
		if (memento != null) {	
			memento.putInteger(TAG_LAYOUT, getLayoutAsInt());
		} else {
		
			IPreferenceStore store= JavaPlugin.getDefault().getPreferenceStore();
			store.setValue(TAG_LAYOUT, getLayoutAsInt());
		}
	}
	private int getLayoutAsInt() {
		if (fIsCurrentLayoutFlat)
			return FLAT_LAYOUT;
		else
			return HIERARCHICAL_LAYOUT;
	}
	protected void saveScrollState(IMemento memento, Tree tree) {
		ScrollBar bar= tree.getVerticalBar();
		int position= bar != null ? bar.getSelection() : 0;
		memento.putString(TAG_VERTICAL_POSITION, String.valueOf(position));
		
		bar= tree.getHorizontalBar();
		position= bar != null ? bar.getSelection() : 0;
		memento.putString(TAG_HORIZONTAL_POSITION, String.valueOf(position));
	}
	protected void saveSelectionState(IMemento memento) {