Clear file tree context when context menu item is selected.

This is a fix for #9228.
Fix click handling for file tree rename inputs.

Fix for #9217.
context mouse down was blocking clicks on the rename input.
Add missing space in classes on file node.

Fix for #9264.
Make sure context bar is positioned properly when focused on working set.
Replace magic number 2 with a MIDDLE_MOUSE_BUTTON constant
-merged master
Merge pull request #9265 from adobe/dangoor/rename-issues

File tree rename issues fix, part 1