unicode-range incorrectly rejects some values should be valid when scientific syntax involves

```html
<!DOCTYPE HTML>
<style>
@font-face { unicode-range: U+4E00-9FFF; }
</style>
<script>
alert(document.styleSheets[0].cssRules[0].style.getPropertyValue('unicode-range'));
</script>
```
or `U+4E-9F`.