fix some working set view issues

Fixes #9019 
Fixes #8973
Fixes #9032
Fixes #9142
Fix for #9032 looks good except for 1 quirk with single select.

1. Split View, Open 4 files -- 2 in each pane
2. In project tree, single-click file that is open in *current* working set, but *not* displayed in editor.

Results:
File is selected in project tree. File is displayed in editor. This is same as 0.43

3. In project tree, single-click file in the *other* working set that is *not* displayed in editor.

Results:
File is selected in project tree. File is displayed in editor. This is same as 0.43

4. In project tree, single-click file in the *other* working set that *is* displayed in editor.

Results:
File is selected in **working set**.

Expected:
File is selected in project tree.