Somehow, the arrow go-to-link icon thing is disappearing shortly after hovering over a row. So, it's hard to catch it to cause the DOM element to be revealed in the content view. We should also show the element when its row is double-clicked.
Maybe fixed by removing LayerTreeDataGrid?
Hooking up double-click sounds good too.
If I recall, LayerTreeDataGrid exists because it provides better sorting that was too scary to integrate in DataGrid.
DataGrid now has said sorting and LayerTreeDataGrid was removed.
http://trac.webkit.org/changeset/165487
<rdar://problem/28228566>