Implement addDamage in Unmanaged

For Xwayland Unmanaged needs to override the addDamage method and
update the repaints_region accordingly, otherwise the repaint is not
triggered for the Unmanaged window.

Reviewed-By: bshah

unmanaged.cpp

@@ -154,5 +154,11 @@ NET::WindowType Unmanaged::windowType(bool direct, int supportedTypes) const
     return info->windowType(NET::WindowTypes(supportedTypes));
 }
 
+void Unmanaged::addDamage(const QRegion &damage)
+{
+    repaints_region += damage;
+    Toplevel::addDamage(damage);
+}
+
 } // namespace
 

unmanaged.h

@@ -51,6 +51,7 @@ public Q_SLOTS:
     void release(ReleaseReason releaseReason = ReleaseReason::Release);
 protected:
     virtual void debug(QDebug& stream) const;
+    void addDamage(const QRegion &damage) override;
 private:
     virtual ~Unmanaged(); // use release()
     // handlers for X11 events