'=' in /**/ comment after arrow( => ) is not correctly transpiled

NG
`
let a = () => /* = */ {
return 'b'
}
`

OK
`
let a = () => { /* = */
return 'b'
}
`

OK
`
let a = () /* = */ => {
return 'b'
}
`

I found this issue in [@material/select/foundation.js L55 ( Material components web )](https://github.com/material-components/material-components-web/blob/master/packages/mdc-select/foundation.js)

Reproduce the issue with the three arrow-function examples in the report and compare the transpiled output, focusing on the case where /* = */ follows the arrow. Inspect the referenced Material Components Web foundation.js line 55 for the real-world input. Done means the comment is transpiled correctly without changing the valid examples.

Written by the indexing model from the issue text.