replace node classList with dataset

[cezaraugusto]

fix #10443
unblocks #10234

1. have enough bookmarks to show the overflow indicator
2. click the overflow, should open
3. open a bookmark pull down with children
4. you should be able to click the second level child
5. second level child should be nested visually with its parent

[codecov-io]

Codecov Report

Merging #10445 into master will decrease coverage by <.01%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master   #10445      +/-   ##
==========================================
- Coverage   53.81%   53.81%   -0.01%     
==========================================
  Files         238      238              
  Lines       21054    21053       -1     
  Branches     3258     3258              
==========================================
- Hits        11330    11329       -1     
  Misses       9724     9724

Flag	Coverage Δ
#unittest	53.81% <ø> (-0.01%)	⬇️

Impacted Files	Coverage Δ
app/renderer/components/common/browserButton.js	69.04% <ø> (-0.72%)	⬇️

[luixxiul]

The test plan works, thanks.

[srirambv]

Not seeing any second level child due to #12052

[srirambv]

@cezaraugusto Is this expected?

[cezaraugusto]

can't see a bug in the screenshot what's missing?

[srirambv]

The nested items open on to the left used to be right

[cezaraugusto]

ya it's expected because the parent menu is on the right. Chrome does the same