xcb: Properly process enter/leave events

Ignore enter/leave events when there is a window under mouse button.
Unset window under mouse button if other window is grabbed.
Smarter ignoring (un)grab ancestor enter/leave event.
Ignore ungrab inferior leave event.

Amends: b9f76db30d261421e4da58f29053181af04ceb4d

Task-number: QTBUG-46576
Task-number: QTBUG-51573
Task-number: QTBUG-52332
Task-number: QTBUG-52488
Change-Id: I8d926309aa60bb8929728691c31ecf93d1e299ad
Reviewed-by: Dmitry Shachnev <mitya57@gmail.com>
Reviewed-by: Laszlo Agocs <laszlo.agocs@theqtcompany.com>
Reviewed-by: Shawn Rutledge <shawn.rutledge@theqtcompany.com>

1 files changed, 3 insertions, 0 deletions

diff --git a/src/plugins/platforms/xcb/qxcbconnection.h b/src/plugins/platforms/xcb/qxcbconnection.h
index 86af5dc9c5..7ba95887ff 100644
--- a/src/plugins/platforms/xcb/qxcbconnection.h
+++ b/src/plugins/platforms/xcb/qxcbconnection.h
@@ -475,6 +475,8 @@ public:
     void setFocusWindow(QXcbWindow *);
     QXcbWindow *mouseGrabber() const { return m_mouseGrabber; }
     void setMouseGrabber(QXcbWindow *);
+    QXcbWindow *mousePressWindow() const { return m_mousePressWindow; }
+    void setMousePressWindow(QXcbWindow *);
 
     QByteArray startupId() const { return m_startupId; }
     void setStartupId(const QByteArray &nextId) { m_startupId = nextId; }
@@ -658,6 +660,7 @@ private:
 
     QXcbWindow *m_focusWindow;
     QXcbWindow *m_mouseGrabber;
+    QXcbWindow *m_mousePressWindow;
 
     xcb_window_t m_clientLeader;
     QByteArray m_startupId;