ext/standard: request_parse_body - change invalid content-type header exception to RequestParseBodyException

[Ayesh]

Currently, request_parse_body function throws an InvalidArgumentException exception if the request Content-Type header is invalid or of an unknown type such as application/json.

To make this consistent with other exception conditions, this changes the exception type from InvalidArgumentException to RequestParseBodyException.

[bukka]

I think it makes sense. It would be actually also good to not have the exception in zend but rather some exception defined in standard ext as it is standar specific.

Ping for @iluuu1994 in case there is some good reason to use InvalidArgumentException that I'm missing.

[Girgias]

This makes sense to me.

I would rather not have SPL exceptions used anywhere outside of SPL, as a lot of them can be converted to user ValueErrors.

[iluuu1994]

According to the RFC, it should be the other way around, both should be InvalidArgumentExceptions. Admittedly, given that the content-type is no longer an argument, the exception doesn't make too much sense anymore. I'm ok with switching both to RequestParseBodyException, but maybe send a quick e-mail to the list (if it works, that is 😋).

[iluuu1994]

I think it makes sense. It would be actually also good to not have the exception in zend but rather some exception defined in standard ext as it is standar specific.

The reason it's there is because it's not just referenced from ext but also main. We generally don't do that from Zend, but I see there's already references to ext from main. TBH the separation of ext/standard, main and Zend is largely arbitrary.