`suppressErrors` + `withPositions` is causing Exception on wrong expressions

[mkslanc]

Hi! I am trying to replace underlying library for php diagnostics for ace-linters, and meet this bug.
Minimal reproducible example:

<?php
fu1nction nfact($n) {
    if ($n == 0) {
        return 1;
    }
    else {
        return $n * nfact($n - 1);
    }
}
?>

on

{
            parser: {
                extractDoc: false,
                suppressErrors: true,
            },
            ast: {
                withPositions: true,
                withSource: false,
            },
            lexer: {
                all_tokens: false,
                comment_tokens: false,
                mode_eval: false,
                asp_tags: false,
                short_tags: true, // allow `<?` if needed
            },
        }

will cause

TypeError: Cannot read properties of undefined (reading 'loc')
    at AST.swapLocations (php-parser.js:189:30)
    at AST.resolvePrecedence (php-parser.js:323:10)
    at result (php-parser.js:381:17)
    at Parser$1.read_statement (php-parser.js:10206:18)
    at Parser$1.read_top_statement (php-parser.js:9896:21)
    at Parser$1.read_start (php-parser.js:9175:19)
    at Parser.parse (php-parser.js:6566:22)
    at Engine.parseCode (php-parser.js:4349:22)
    at PhpService.doValidation (php-service.ts:61:38)
    at service-manager.ts:57:31

on my service using your lib as an engine.

Setting withPositions to false or suppressErrors to false would lead to normal behaviour, though without precise positions of course.