RFR: 8280990: [XWayland] XTest emulated mouse click does not bring window to front

[Prasanta Sadhukhan]

On Tue, 28 May 2024 02:25:46 GMT, Alexander Zvegintsev <azvegint at openjdk.org> wrote:

> Some of the modal tests fail in X11 compatibility mode on Wayland, because a mouse click emulated with XTEST does not not cause the windows to be reordered.
> 
> This is a known limitation because these click events do not leave the XWayland server and are not reported to the Wayland compositor.
> 
> There is a [libei](https://gitlab.freedesktop.org/libinput/libei) that can be used to emulate input events in Wayland.
> And there is a [bridge that allows emulated events from XTEST to be passed to the compositor](https://gitlab.freedesktop.org/libinput/libei/-/blob/main/README.md?ref_type=heads#xwayland-and-xtest).
> Support for this has been added in [Gnome 45 and XWayland 23.2](https://gitlab.gnome.org/GNOME/mutter/-/issues/3194#note_1937109), but it is optional and not yet enabled in Ubuntu.
> 
> This change adds `toFront` calls for mouse clicks that are only intended to bring a window to the front in the window stacking order.
> 
> The testing is green on all platforms.

WIll it be a problem if we use toFront for the frame anyways? We have seen and done tofront() for many tests where the frame gets obscured by some other window so mouseclicks was not on desired area

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Marked as reviewed by psadhukhan (Reviewer).

PR Review: https://git.openjdk.org/jdk/pull/19417#pullrequestreview-2090670877