Internal refactor: remove the Parser::exhausted boolean flag.
Internal refactor: remove the Parser::exhausted boolean flag.

It wasn’t really necessary, and confusigly had a different meaning than Parser::is_exhausted().

notriddle/rust-cssparser,frewsxcv/rust-cssparser,tempbottle/rust-cssparser,servo/rust-cssparser,servo/rust-cssparser,tempbottle/rust-cssparser,frewsxcv/rust-cssparser,disjukr/rust-cssparser,disjukr/rust-cssparser,notriddle/rust-cssparser