A while ago I simplified the HTML output for the tree. At one point we output the label as <span>label</span>. The span was removed and the label simply appears next to the icon image.
The TreeHtmlAttribute supported setting attributes on the <span>
through the onLabelLink attribute. In addition, the onIconLink was used to set HTML attributes on the anchor used for selection.
All of the attribute test actually set that attribute which is the reason it looked like we were not actually setting attributes correctly.
In this fix, removed the onLabelLink from TreeHtmlAttribute and also renamed the onIconLink to onSelectionLink.
I also updated all of the tests so that they use onSelectionLink now and verified the test results.