Resizing window when mouse cursor confined uses old area.

[ghost]

v3.1.alpha_custom_build.93a888e

When your cursor mode is CONFINED and you resize the window, the confinement area is stuck as the last window size from what it looks like.

Example Project:
Mouse Confine and Resize.zip

@capnm @guilhermefelipecgs

I believe this may be an issue as well for other OSes, but so far testing in Windows 10 64-bit.

Might be tying into: #21751 and #21744

[guilhermefelipecgs]

Linux works fine.