Add virtual stub to QAbstractEventDispatcherV2

To be implemented in 6.9, but added here to avoid a
QAbstractEventDispatcherV3.

Change-Id: If8bd98f6299e39999d09b2c8857565d5fd890eec
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(cherry picked from commit 404ad4e17d9d36566881e0f398e24ccbc2af4a72)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>

src/corelib/kernel/qabstracteventdispatcher.cpp

@@ -702,6 +702,16 @@ int QAbstractEventDispatcherV2::remainingTime(int timerId)
     auto self = static_cast<QAbstractEventDispatcherV2 *>(this);
     return fromDuration<int>(self->remainingTime(Qt::TimerId(timerId)));
 }
+
+/*!
+    \internal
+    Temporary compatibility override.
+*/
+bool QAbstractEventDispatcherV2::processEventsWithDeadline(QEventLoop::ProcessEventsFlags flags, QDeadlineTimer deadline)
+{
+    Q_UNUSED(deadline);
+    return processEvents(flags);
+}
 #endif // ! Qt 7
 
 QT_END_NAMESPACE

src/corelib/kernel/qabstracteventdispatcher.h

@@ -108,6 +108,7 @@ public:
     virtual bool unregisterTimer(Qt::TimerId timerId) = 0;
     virtual QList<TimerInfoV2> timersForObject(QObject *object) const = 0;
     virtual Duration remainingTime(Qt::TimerId timerId) const = 0;
+    virtual bool processEventsWithDeadline(QEventLoop::ProcessEventsFlags flags, QDeadlineTimer deadline); // reserved for 6.9
 
 protected:
     QAbstractEventDispatcherV2(QAbstractEventDispatcherPrivate &, QObject *parent);