Bug 93360 [Viewers] getChild still used in indexForElement
indexForElement() in AbstractTreeViewer still uses getChild() and not getChildren(). This should probably also change to using getChildren() and do the same thing as insertionPosition().
bundles/org.eclipse.jface/src/org/eclipse/jface/viewers/AbstractTreeViewer.java
for (int i = 0; i < min; ++i) {
            Item item = items[i];
            Object oldElement = item.getData();
            if (oldElement != null) {
                Object newElement = elementChildren[i];
                if (newElement != oldElement) {
                    if (equals(newElement, oldElement)) {
                        
                        
                        
                        
                        item.setData(newElement);
                        mapElement(newElement, item);
                    } else {
                        disassociate(item);
                        
                        item.setImage(null);
                        item.setText("");
                    }
                }
            }
        }
        for (int i = 0; i < min; ++i) {
            Item item = items[i];
            Object newElement = elementChildren[i];
            if (item.getData() == null) {