Bug 171649 [Viewers] AbstractTreeViewerisExpandable(elementOrTreePath) is not called when using a ITreePathContentProvider
Build ID: 3.3M3 More information: see AbstractTreeViewer.java, line 1974, the content provider hasChildren() should not be called directly
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
/**
	 * Returns the number of columns of this viewer.
	 * <p><b>Subclasses should overwrite this method, which has a default
	 * implementation (returning 0) for API backwards compatility reasons</b></p>
	 *
	 * @return the number of columns
	 *
	 * @since 3.3
	 */
	protected int doGetColumnCount() {
		return 0;
	}
	
	
	/**
	 * This implementation of buildLabel handles tree paths as well as elements.
	 * 
	 * @param updateLabel
	 *            the ViewerLabel to collect the result in
	 * @param elementOrPath
	 *            the element or tree path for which a label should be built
	 * 
	 * @see org.eclipse.jface.viewers.StructuredViewer#buildLabel(org.eclipse.jface.viewers.ViewerLabel,
	 *      java.lang.Object)
	 */
	protected void buildLabel(ViewerLabel updateLabel, Object elementOrPath) {
		Object element;
		if (elementOrPath instanceof TreePath) {
			TreePath path = (TreePath) elementOrPath;
			IBaseLabelProvider provider = getLabelProvider();