Bug 156544 [Viewers] Vitrual lazy tree viewer - refreshing a node does not make it expandable
I20060830-1650 Using a tree viewer with the SWT.Vitrual style and an ILazyTreeContentProvider. If a node in a tree has no children in an underlying model, and then has children added to that node, calling refresh no the corresponding element does not add a "+" to the tree node. The code that does not consult the content provider for an element's child count if a tree item already has data mapped to it. Attatched is a sample plug-in showing the problem. The model changes from: root one two three to: root one a b c two three ... but the content provider is not consulted when calling refresh on "one". To see the problem, open the sample view, and invoke "Update Model" action from the context menu.
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/TreeViewer.java
treeViewerImpl.setCellEditors(editors);
	}
	/**
	 * Sets the cell modifier of this tree viewer.
	 * 
	 * @param modifier
	 *            the cell modifier
	 * @since 3.1
	 */
	public void setCellModifier(ICellModifier modifier) {
		treeViewerImpl.setCellModifier(modifier);
	}
	/**
	 * Sets the column properties of this tree viewer. The properties must
	 * correspond with the columns of the tree control. They are used to
	 * identify the column in a cell modifier.
	 * 
	 * @param columnProperties
	 *            the list of column properties
	 * @since 3.1
	 */
	public void setColumnProperties(String[] columnProperties) {
		treeViewerImpl.setColumnProperties(columnProperties);
	}
	/*
	 * (non-Javadoc) Method declared in AbstractTreeViewer.
	 */
	protected void setExpanded(Item node, boolean expand) {
		((TreeItem) node).setExpanded(expand);
		if (getContentProvider() instanceof ILazyTreeContentProvider) {