mime: be stricter parsing media types

[bradfitz]

This shouldn't be valid:

http://play.golang.org/p/IQ8GeEmP1_

    t, params, err := mime.ParseMediaType(`image/'><style type="text/css">td{background-color:red}</style>`)   
    fmt.Printf("t=%q, p=%v, err=%v", t, params, err)

        t="image/'><style type=\"text/css\">td{background-color:red}</style>", p=map[], err=mime: unexpected content after media subtype


according to: http://www.ietf.org/rfc/rfc1521.txt

[rsc]

Comment 1:

It's not valid: there's an error returned.

[bradfitz]

Comment 2:

yeah, but it'd still be nice if t and params were zero values when err != nil.  I know
that's not documented, but it's more consistent with how errors normally work, and it's
halfway implied by the docs saying that a non-nil map is returned when err == nil.
Feel free to close if you disagree.

[rsc]

Comment 3:

agreed

[bradfitz]

Comment 4:

This issue was closed by revision 7f7a70f.

Status changed to Fixed.

[rsc]

Comment 5:

This issue was closed by revision b0c2507ec455.