Fix 404 page widget script URL

[alfredxing]

Fix 404 page widget script URL to be compatible with HTTPS by replacing http:// with //.

I checked the src and Google does have a hosted copy on SSL (https://linkhelp.clients.google.com/tbproxy/lh/wm/fixurl.js).

[necolas]

Looks good to me. I can't remember if there is a reason for this not to be protocol relative, but if there is, I couldn't find it.

Also, thanks for the great commit message in line with the contribution guidelines. Having clear explanations in the commit messages makes all the difference when you have to do some archaeology on a codebase. Much appreciated.

[necolas]

Merged in a104609

[alfredxing]

I don't the code Google provided was not protocol relative...

Thanks!

[mathiasbynens]

Did anyone verify this code doesn’t suffer from the same problem as the Google Analytics snippet? See #1319. (As long as we still support IE6…)

[necolas]

No.

[mathiasbynens]

I still haven’t tested this in IE6, but it seems to be alright:

$ echo -e "GET / HTTP/1.1\nEOT" | openssl s_client -connect linkhelp.clients.google.com:443 2>&1 | grep subject
subject=/C=US/ST=California/L=Mountain View/O=Google Inc/CN=*.google.com

linkhelp.clients.google.com matches *.google.com, so this change shouldn’t cause any errors, not even in IE6. (Bash snippet from http://mathiasbynens.be/notes/async-analytics-snippet#comment-29.)