auto-save and null request patch for terrible adware

[duane-r]

I made this patch to get past some really ugly adware that's popped up in several places. The changes allowed me to implement some of ublock's rules. I can make a pull request if anyone is interested, but it's fairly esoteric.

The first part modifies the "send-request" signal to take "null" as a response, which stops the request and also prevents the browser from reloading the page. This allows a download from javascript to occur.

The second part is more generally useful. It lets you return "download" from the "mime-type-decision" signal to force a download of some media on some site, even if gstreamer could play it -- which lets me save the javascript download.

Environment:

Linux Distribution & Version:
gentoo

Output of luakit --version:
luakit 2.3.3
built with webkit 2.40.3 (installed version: 2.40.3)

null-redirect.patch.zip