Fixed printable char detection for unicode > 0xFFFF

[ysavary]

Fixes #587

[puzrin]

Solved in more old-school way - with keeping older browsers support.

[rlidwka]

Thanks for sending this PR.

It didn't quite work for us, since neither Array.from() nor String.prototype.codePointAt() are present in old browsers. So this issue was fixed slightly differently (with polyfill for codePointAt), see 0b2e702.

Array.from() isn't needed here at all, since it can be replaced with an iteration like this:

/*
var chars = Array.from(string);
for (var i = 0; i < chars.length; i++) {
  var code = chars.codePointAt(0);
}
*/

for (var i = 0; i < string.length; i++) {
  var code = string.codePointAt(i);
  if (code >= 0x10000) i++;
}

... which does the same thing, but works faster.

[ysavary]

Thank you @rlidwka for your fix !