dijit._TreeNode widgets do not have own focused/blured events

[alex]

in extending the dijit._TreeNode class to give it new formatting, I was surprised to find that the _onNodeFocus() event delegates to the containing tree widget which reaches into the nodes themselves to set and un-set WAI roles and states and the various css rules. This seems poorly factored. It should be the TreeNodes?' responsibility to respond to focus and blur events and set styles accordingly. No backwards-incompatible changes need to be made to make this happen.

[bill]

Looks like it TreeNode? calls Tree._onNodeFocus() so that:

1. Tree can blur the currently focused node
2. Tree keeps track of the currently focused node

I can see putting the styling code into _TreeNode though.

[bill]

bumping 1.4 tickets to 1.5, and most 1.3 tickets to 1.4

[bill]

This code is a bit tangled up, and not trivial to fix. Focus is fairly simple but there are two types of "blur" operations:

• in blurNode(), where focus is moved to another TreeNode?
• in _onBlur(), where focus has been moved away from the whole tree

In the former case we are setting tabIndex to -1, but not in the latter case.

It's because Tree has a concept of a currently selected node, same as TabContainer? has a currently selected tab, even when focus is somewhere away from the tree.

[bill]

CC'ing becky in case she wants to look over the change I am checking in.

[bill]

Refactor completed in [16123].