mail build: support webkit2gtk-4.1

Just packaged evolution-data-server 3.45.1 and built this, seems to work. But I am really not sure what I am doing, @decathorpe can you help test this a bit?

Closes #793

Jul 22 '22 12:07 bobby285271

Have you checked whether this code actually still compiles with older versions of e-d-s? For example, I'm not sure whether replacing all uses of Soup.URI with Glib.Uri is compatible with both cases, and we might need conditional compilation.

Jul 23 '22 08:07 decathorpe

Ugh... Actually this (6320081c781786cf08b3ce8dc37709f7eeb8649f) still builds and runs for me on nixos-unstable (with everything GNOME 42 e.g. e-d-s 3.44.3). For Soup.URI -> GLib.Uri, I actually think that is compatible for both cases, for example gnome-software is updating that unconditionally when doing a conditional port :thinking:. I can update that if requested, give me a sec :-)

Jul 23 '22 09:07 bobby285271

I can confirm that this PR fixes the build against evolution-data-server 3.45+ with webkit2gtk-4.1, and keeps building with earlier versions.

Jul 26 '22 19:07 decathorpe

The patch from this PR no longer applies on top of the master branch, can you please rebase?

Aug 05 '22 08:08 decathorpe