Remove QUpdateEvent from the public headers

It's only used internally in qwidget, so it might as well
live in qwidget_p.h.

Task-number: QTBUG-25070, QTBUG-25373
Change-Id: I87770e0b49253b4bdebe90ce84dd42448d6175bd
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/gui/kernel/qevent.cpp

@@ -1073,15 +1073,6 @@ QPaintEvent::~QPaintEvent()
 */
 
 
-QUpdateLaterEvent::QUpdateLaterEvent(const QRegion& paintRegion)
-    : QEvent(UpdateLater), m_region(paintRegion)
-{
-}
-
-QUpdateLaterEvent::~QUpdateLaterEvent()
-{
-}
-
 /*!
     \class QMoveEvent
     \brief The QMoveEvent class contains event parameters for move events.

src/gui/kernel/qevent.h

@@ -326,19 +326,6 @@ protected:
     bool m_erased;
 };
 
-// ### Qt5: make internal
-class Q_GUI_EXPORT QUpdateLaterEvent : public QEvent
-{
-public:
-    explicit QUpdateLaterEvent(const QRegion& paintRegion);
-    ~QUpdateLaterEvent();
-
-    inline const QRegion &region() const { return m_region; }
-
-protected:
-    QRegion m_region;
-};
-
 class Q_GUI_EXPORT QMoveEvent : public QEvent
 {
 public:

src/widgets/kernel/qwidget_p.h

@@ -88,6 +88,25 @@ class QUnifiedToolbarSurface;
 // implemented in qshortcut.cpp
 bool qWidgetShortcutContextMatcher(QObject *object, Qt::ShortcutContext context);
 
+class QUpdateLaterEvent : public QEvent
+{
+public:
+    explicit QUpdateLaterEvent(const QRegion& paintRegion)
+        : QEvent(UpdateLater), m_region(paintRegion)
+    {
+    }
+
+    ~QUpdateLaterEvent()
+    {
+    }
+
+    inline const QRegion &region() const { return m_region; }
+
+protected:
+    QRegion m_region;
+};
+
+
 
 class Q_AUTOTEST_EXPORT QWidgetBackingStoreTracker
 {