Fix stickynotes

[lukefromdc]

Fix failure of stickynotes to show in both x11 and wayland, and wayland segfaults. Do not use GtkSourceView anymore since the current version is not working with stickynotes, use GtkTextView which works fine even if it has fewer features.

Also ensure that when in Wayland (or any future non-x11 windowing system) we don't call x11 specific functions

[lukefromdc]

Possible fix for
#668

[lukefromdc]

Once again, we've got travis problems different from before and in at least four attempts I have not been able to fix them. Giving up on that for tonight. After my last try curl wasn't found for some reason Same in master though, will force-push just to keep this synched.

This can be merged if reviews are positive, but to create a new release I will again need help with travis

[robertkirkman]

Thank you very much this worked to fix the problem for me! "New Note" now works, and the applet does not crash anymore.

[lukefromdc]

Just to help with getting the broadest range of testing, do you build mate-applets with the applets out of process(the default) or (newly supported for wayland compatabiity) in-process? Since you were getting applet crashes and not the whole panel crashing I am presuming you built the applet out of process as a crashing in-process applet takes down the whole panel.

I tested an in-process build compatable with wayland, in both x11 and in wayland and it worked both ways. If you built it out of process, we now have verification this works both ways. In that case I will wait a bit to see if any other team member wants to review it, and if not will merge it,

Distros probably won't pick it up until a new release though, and that requires fixing (again) the travis problems. I don't have any other way to push packages made by make distcheck to https://pub.mate-desktop.org/

[robertkirkman]

I use Xorg, so I guess that means they are out-of-process for me (it is named /usr/libexec/mate-applets/stickynotes-applet for me so I think that's what that means?)

[lukefromdc]

Confirm, that means you built them out of process.That works only in Xorg, MATE's default, and the PR worked for you in that build. In-process is compatable with both Xorg and Wayland and that build works for me. That verifies I didn't create a fix that only works one way.

[lukefromdc]

1.28.1 containing this fix is now available, distros offering 1.28 should pick it up soon
https://pub.mate-desktop.org/releases/1.28/mate-applets-1.28.1.tar.xz