Made changes exactly like what eslint would do automatically. I made this commit by pasting tree.js in another project that already had eslint installed, and I ran the linter, then I pasted the code back.
Made changes exactly like what eslint would do
automatically. I made this commit by pasting tree.js in another project
that already had eslint installed, and I ran the linter, then I pasted
the code back.

eweitnauer/tree.js,eweitnauer/tree.js