Bug 174701 [Viewers] ViewerRow should be reused instead of connected to the Item
Currently we create a ViewerRow ver every Item we create this can degrade performance, we should cache the row and reuse it
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
*/
	protected void showItem(Item item) {
		getTree().showItem((TreeItem) item);
	}
	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.jface.viewers.AbstractTreeViewer#getChild(org.eclipse.swt.widgets.Widget,
	 *      int)
	 */
	protected Item getChild(Widget widget, int index) {
		if (widget instanceof TreeItem) {
			return ((TreeItem) widget).getItem(index);
		}
		if (widget instanceof Tree) {
			return ((Tree) widget).getItem(index);
		}
		return null;
	}
	protected void assertContentProviderType(IContentProvider provider) {
		if (provider instanceof ILazyTreeContentProvider
				|| provider instanceof ILazyTreePathContentProvider) {
			return;
		}
		super.assertContentProviderType(provider);
	}
	protected Object[] getRawChildren(Object parent) {
		if (contentProviderIsLazy) {
			return new Object[0];
		}