Fix panic on Wayland

[bi4k8]

When running current ruffle HEAD on Wayland, I get an error popup with the following contents:

Ruffle has encountered a fatal error, this is a bug.

panicked at desktop/src/player.rs:147:22:
Couldn't create ui backend: Couldn't get platform clipboard

Caused by:
Unknown error while interacting with the clipboard: Display parsing error

Please report this to us so that we can fix it. Thank you!

This appears to be caused by using the "arboard" crate without the feature flag required for its Wayland support: 1Password/arboard#98

This PR enables this feature and fixes the panic.

[n0samu]

Thanks so much! I think this should also help unblock #9220.

[torokati44]

Thank you, and welcome to the project!

Interestingly, I've been running Ruffle on Wayland for well over a year now, and never had any issues with it, even the clipboard works just fine (at least for text), both in Weston and KDE.

But this is entirely fine to do, if it indeed helps others, and even the Flatpak issue linked above.

One thing is, please tag the commit messages as advised by CONTRIBUTING.md. I'll fix it this time, as I'm going to squash your commits on merge anyway.

[bi4k8]

Interestingly, I've been running Ruffle on Wayland for well over a year now, and never had any issues with it, even the clipboard works just fine (at least for text), both in Weston and KDE.

If you have XWayland around, clipboard integration probably worked for you through the X11 codepaths. I don't use XWayland so I noticed the missing native clipboard support.

One thing is, please tag the commit messages as advised by CONTRIBUTING.md. I'll fix it this time, as I'm going to squash your commits on merge anyway.

My mistake--I'll follow convention if I have anything else to PR. Thanks for the project!