[regression] Tree: error when clicking above/below TreeNodes

[spaquette]

Looks like this started after [30808]. If you place a Tree inside a ContentPane whose size is larger than the Tree needs, there can be extra space above/below the Tree. If you click in this space in 1.9.0a2 or 1.8, there's no error, but starting after [30808], there's this:

Uncaught TypeError: Cannot read property 'id' of null (_dndSelector.js:199)

(My test example needs a copy of trunk to show the bug.)

[spaquette]

Example of Tree-in-ContentPane? clicking bug

[spaquette]

The problem might be this at _dndSelector.js:190:

if(this.current && this.tree.isExpandoNode(e.target, this.current)){ return; }

It was this previously:

if(!this.current || this.tree.isExpandoNode(e.target, this.current)){ return; }

If I revert that the error stops, maybe because the previous version was also catching and ignoring clicks outside the Tree's rows that still landed on the Tree's DIV, but the current version doesn't.

[bill]

I see, makes sense, thanks.

[bill]

In [30852]:

avoid exception when clicking on the Tree itself rather than a row in the tree, fixes #16839 !strict