remove predefined values from cubic-bezier()

[myakura]

looks like 1295cfe#diff-0 unintentionally introduced these predef values. so taking them out.

[abose]

Thanks @myakura for contributing to brackets.
The Contributor License Agreement should be signed before we can accept the change.

[nethip]

@redmunds Would you mind reviewing this change?

[petetnt]

I think those values are be intentional: the values are equivalent to ease-in-out, which is often used* as the default value for cubic-bezier curves because it nicely shows what it's meant for. Other default would be equal to linear (0,0,1,1), which isn't that nice IMO.

• citation needed, might just be my own opinion.

[nethip]

Thanks @petetnt for quickly jumping in and trying to analyze this 👍

[redmunds]

@nethip Yes, @petetnt is correct about the original reason for using predefined values. But, I think that @marcelgerber fixed it so that cubic-bezier() will now give the same result, so predefined values may no longer be necessary.

[myakura]

@abose thx. signed!

[abose]

Merged for 1.6. Thanks @myakura