First token after class should use previous strict-mode state

[pvdz]

This is the same bug as Babel: babel/babel#11183

I guess when parsing the } closing token of a class, the next token is still parsed as the strict-mode context from that class, rather than using the outer strict mode status.

In script mode, this (a legacy octal) passes in Acorn/Babel (because it applies annexb by default):

05

This fails after a class:

class x {}
05

But passes with anything in between:

class x {}
y
05

(All the above cases should pass in non-strict script mode under annexb rules)

acorn@7.1.0