Summary:
This fixes the following problem:
1. Have two windows maximized
2. Click minimize button on first window
3. Click minimize button on second window

What happened:
Second click was ignored as the pointer was not updated.

BUG: 378704
FIXED-IN: 5.11

Test Plan:
Nested KWin/Wayland, added two maximized windows, minimized
both without moving the mouse

Reviewers: #kwin, #plasma

Subscribers: plasma-devel, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D8145