Ensure leave event is send to decoration when a window maximizes

Summary:
When clicking the maximize button without moving the mouse, the maximize
button stayed in hover state till the mouse moved. The reason for this
is that the PointerInputRedirection does not perform an update on the
geometry change of a window.

BUG: 385140
FIXED-IN: 5.11

Test Plan: Manual testing

Reviewers: #kwin, #plasma

Subscribers: plasma-devel, kwin

Tags: #kwin

Differential Revision: https://phabricator.kde.org/D8016