Bug 32254 [Viewers] AbstractTreeViewer uses HashSet to remember expansion state
I20030216 The custom hash table should be used instead. Otherwise expansion state may be lost due to a different equals implementation of the element and the IElementComparer.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
} else {
		ILabelProvider provider = (ILabelProvider)baseProvider;
		item.setText(provider.getText(element));
		Image image = provider.getImage(element);
		if (item.getImage() != image) {
			item.setImage(image);
		}
	}
	if (baseProvider instanceof IColorProvider) {
		IColorProvider cp = (IColorProvider) baseProvider;
		TreeItem treeItem = (TreeItem) item;
		treeItem.setForeground(cp.getForeground(element));
		treeItem.setBackground(cp.getBackground(element));
	}
	if (baseProvider instanceof IFontProvider) {
	    IFontProvider fprov = (IFontProvider) baseProvider;
	    TreeItem treeItem = (TreeItem) item;
	    treeItem.setFont(fprov.getFont(element));
	}			
}
/* (non-Javadoc)
 * Method declared in AbstractTreeViewer.
 */
protected Item[] getChildren(Widget o) {
	if (o instanceof TreeItem)
		return ((TreeItem) o).getItems();
	if (o instanceof Tree)
		return ((Tree) o).getItems();
	return null;