Comment 3 for bug 1578512

To clarify, with this patch in place the filename will be properly escaped in the HTTP response header, like this:

Content-Disposition: attachment; filename="t\"est.txt"

Depending on your browser and operating system, the quote marks in the filename may not actually wind up as quote marks. For instance, running my test in Firefox on Ubuntu, the double quotes are changed into underscores. (Which is still an improvement over the filename being truncated or omitted as it was before this patch.)