Knob mixin

[edu-aguilar]

added needed mixins to style the component from outside.

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[edu-aguilar]

I signed in cla.developers.google

[googlebot]

CLAs look good, thanks!

[keanulee]

Hi @edu-aguilar , can you give some use cases on how these mixins will be used? Adding unnecessary mixins to the implementation of an element defeats the purpose of encapsulating implementation details.

[edu-aguilar]

hi @keanulee first of all, thanks for your fast reply. Im working in a component that wraps this one and i need those mixins to apply styles from outside. Specially, to remove margins that I dont need and set a custom height and width to knob.

I think this could be useful for other devs =)

Thanks!