Update content model of <rp> (#351)
Update content model of <rp> (#351)

See https://github.com/whatwg/html/issues/1689.
takenspc/validator,takenspc/validator,takenspc/validator,tripu/validator,validator/validator,tripu/validator,takenspc/validator,takenspc/validator,validator/validator,validator/validator,tripu/validator,tripu/validator,validator/validator,validator/validator,tripu/validator