Function parse_declaration_value_block 

fn parse_declaration_value_block(
    input: &mut Parser<'_>,
    input_start: SourcePosition,
    namespaces: Option<&FxHashMap<Prefix, Namespace>>,
    references: &mut References,
    missing_closing_characters: &mut String,
) -> Result<(TokenSerializationType, TokenSerializationType), ParseError>

Like parse_declaration_value, but accept ! and ; since they are only invalid at the top level.