Windows QPA: Fix dock widget drag&drop failure

A previous change to fix QTBUG-85431 has caused this issue by emulating
the behavior of the non-enhanced mouse event handler in a particular
case, where mouse move events that did not change position were ignored.
However, some of these events seem to be involved in the dock drag&drop
implementation. This issue is also reproduced in pre-5.15 releases,
predating the QTBUG-85431 fix, by disabling the enhanced mouse event
handler by setting the QT_QPA_DISABLE_ENHANCED_MOUSE env var. However,
the ignored events in the current issue seem to be non-client events
only, while the QTBUG-85431 issue was related to client mouse events.
So we can restrict the test added in the QTBUG-85431 fix and have both
issues fixed.

Fixes: QTBUG-92182
Pick-to: 5.15 6.0 6.1
Change-Id: I98c0c8597912c7f4fe58af375a5a560695a82746
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

1 files changed, 1 insertions, 1 deletions

diff --git a/src/gui/kernel/qguiapplication.cpp b/src/gui/kernel/qguiapplication.cpp
index 966a558304..1905361c5e 100644
--- a/src/gui/kernel/qguiapplication.cpp
+++ b/src/gui/kernel/qguiapplication.cpp
@@ -2169,7 +2169,7 @@ void QGuiApplicationPrivate::processMouseEvent(QWindowSystemInterfacePrivate::Mo
         processMouseEvent(e); // the original mouse event
         return;
     }
-    if (mouseMove && !positionChanged) {
+    if (type == QEvent::MouseMove && !positionChanged) {
         // On Windows, and possibly other platforms, a touchpad can send a mouse move
         // that does not change position, between a press and a release. This may
         // confuse applications, so we always filter out these mouse events for