[checkbox] Material focus outline color is different from the radio-button when unchecked

[vursen]

As discovered in #3031, the Material focus outline color in the checkbox is different from the radio-button when unchecked.

Expected outcome

The focus outline should be the same color in the radio-button and the checkbox.

Actual outcome

The focus outline is differently colored in the radio-button and the checkbox.

[jouni]

AFAIK the color should depend on the checked state of the control (gray when unchecked, purple (primary/accent) when checked).

[web-padawan]

@jouni Thank you for clarification, in this case we probably should update vaadin-radio-button instead 🤔