Material-components-web: mdc-select__menu - overflow-y is set to scroll rather than auto

[RobJacobs]

The mdc-select__menu style has an overflow-y set to scroll causing the scroll bar to appear in the select dropdown whether it's necessary or not: link. Could this be changed to auto instead?

What MDC-Web Version are you using?

0.20.0

What browser(s) is this bug affecting?

All browsers are affected

What OS are you using?

Win 10

What are the steps to reproduce the bug?

A mdc-select with 2 options.

What is the expected behavior?

The vertical scrollbar should only appear when necessary.

What is the actual behavior?

The vertical scrollbar always appears.

Any other information you believe would be useful?

[lynnmercier]

Changing overflow-y to auto sounds reasonable. Would you like to submit a PR?

[RobJacobs]

@lynnjepsen Yes I would.

[trimox]

I'm pretty sure a scrollbar will now be shown during menu's open transition scaling, and disappear if the list is not large. Not sure if that was intended or not?

[RobJacobs]

@trimox @lynnjepsen You are correct. Now that you mention it, I remembered that's why I originally went with setting the max-height to vh units (see discussion in related PR). Let me know if you would like me to create another PR to correct this...

[deap82]

@trimox is right, this can even be seen in the demo: http://material-components-web.appspot.com/simple-menu.html
ping @RobJacobs