Fix rendering of resized XWayland applications with client side decorations

[tarek-y-ismail]

Previously, resizing didn't work at all unless you did a vertical resize followed by a horizontal one (or vice versa). Now, resizes work but only if you shrink the application. Any resizing outside application bounds stops after a couple of pixels.

[AlanGriffiths]

Now, resizes work but only if you shrink the application. Any resizing outside application bounds stops after a couple of pixels

I can confirm this.

The fact this "works" is curious: It implies that some resizing code depends on both new width and new height being supplied. (Not just the dimension(s) that changed.) This might well be the simplest way to accommodate that.

The reason that moving the cursor outside the window stops the resizing is probably that target window loses focus. (With the SSD & wayland windows generally there's "start resize" message passed to the window manager (that initiates a "resize gesture".)

[tarek-y-ismail]

The reason that moving the cursor outside the window stops the resizing is probably that target window loses focus

This will be fixed in another PR. I already had an attempt at fixing it, thinking that the issue was related to input event handling. I'll have another go at it soon™ going for the focus angle.

[AlanGriffiths]

Not necessarily the right thing, but an improvement