Bug 62968 Source folders disappear in Package Explorer if set to Hierarchical Layout
I200405190010 If I set the view to "Hierarchical Layout" in the Package Explorer my "src" folder shows as empty if there are no java files in the root package (i.e. only sub-packages at the first level). Setting to "Flat" and they appear again. Tried a new Java project to recreate, but the problem is not showing on new projects. PB
org.eclipse.jdt.ui/ui/org/eclipse/jdt/internal/ui/packageview/PackageExplorerPart.java
IMemento frameMemento = memento.createChild(TAG_CURRENT_FRAME);
			currentFrame.saveState(frameMemento);
		}
	}
	private void saveLinkingEnabled(IMemento memento) {
		memento.putInteger(PreferenceConstants.LINK_PACKAGES_TO_EDITOR, fLinkingEnabled ? 1 : 0);
	}
	/**
	 * Saves the current layout state.
	 * 
	 * @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) {