PanelView: fix rejecting click events near window edge with HiDPI
When using HiDPI and a click happens near the window edge, the global position might have fractional parts, but after the global position is converted to QPoint, the position can be rounded so it happens to stay at the window edge, so the window geometry will not contain the rounded position.
See also: https://codereview.qt-project.org/c/qt/qtdeclarative/+/548356
BUG: 482580 FIXED-IN: 6.0.3