effects/zoom: Schedule a repaint when window is damaged

This is needed to make per-screen rendering work correctly.

BUG: 431652

effects/zoom/zoom.cpp

@@ -123,6 +123,7 @@ ZoomEffect::ZoomEffect()
     timeline.setFrameRange(0, 100);
     connect(&timeline, &QTimeLine::frameChanged, this, &ZoomEffect::timelineFrameChanged);
     connect(effects, &EffectsHandler::mouseChanged, this, &ZoomEffect::slotMouseChanged);
+    connect(effects, &EffectsHandler::windowDamaged, this, &ZoomEffect::slotWindowDamaged);
 
 #if HAVE_ACCESSIBILITY
     m_accessibilityIntegration = new ZoomAccessibilityIntegration(this);
@@ -519,6 +520,13 @@ void ZoomEffect::slotMouseChanged(const QPoint& pos, const QPoint& old, Qt::Mous
     }
 }
 
+void ZoomEffect::slotWindowDamaged()
+{
+    if (zoom != 1.0) {
+        effects->addRepaintFull();
+    }
+}
+
 void ZoomEffect::moveFocus(const QPoint &point)
 {
     if (zoom == 1.0)

effects/zoom/zoom.h

@@ -84,6 +84,7 @@ private Q_SLOTS:
     void slotMouseChanged(const QPoint& pos, const QPoint& old,
                               Qt::MouseButtons buttons, Qt::MouseButtons oldbuttons,
                               Qt::KeyboardModifiers modifiers, Qt::KeyboardModifiers oldmodifiers);
+    void slotWindowDamaged();
     void recreateTexture();
 private:
     void showCursor();