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
* (non-Javadoc) Method declared in AbstractTreeViewer.
	 */
	protected void removeAll(Control widget) {
		((Tree) widget).removeAll();
	}
	/*
	 * (non-Javadoc) Method declared in AbstractTreeViewer.
	 */
	protected void setExpanded(Item node, boolean expand) {
		((TreeItem) node).setExpanded(expand);
		if (contentProviderIsLazy) {
			
			getControl().update();
		}
	}
	/*
	 * (non-Javadoc) Method declared in AbstractTreeViewer.
	 */
	protected void setSelection(List items) {
		Item[] current = getSelection(getTree());
		
		if (isSameSelection(items, current)) {
			return;
		}
		TreeItem[] newItems = new TreeItem[items.size()];
		items.toArray(newItems);
		getTree().setSelection(newItems);
	}
	/*
	 * (non-Javadoc) Method declared in AbstractTreeViewer.