Add class brand check support

[YuriTu]

View Rendered Text

This PR adds support on stage-1 Proposal-class-brand-check.

This PR is very similar to class property access expressions, but class brand check expressions does not require a static members.

It seems that it can be used as part of class property access expressions.

However, the current Identifier is only hasInstance, maybe others will be added in the future, and it may still need to be separated in the future.

[YuriTu]

I discussed with the author of the proposal and decided it would be like importExpression. so I plan to add a new type of expression: classHasInstanceExpression .