[scripting] Make client.activities writable

abstract_client.h

@@ -79,6 +79,11 @@ class KWIN_EXPORT AbstractClient : public Toplevel
      */
     Q_PROPERTY(bool onAllDesktops READ isOnAllDesktops WRITE setOnAllDesktops NOTIFY desktopChanged)
 
+    /**
+     * The activities this client is on. If it's on all activities the property is empty.
+     */
+    Q_PROPERTY(QStringList activities READ activities WRITE setOnActivities NOTIFY activitiesChanged)
+
     /**
      * The x11 ids for all desktops this client is in. On X11 this list will always have a length of 1
      */
@@ -884,6 +889,7 @@ Q_SIGNALS:
     void demandsAttentionChanged();
     void desktopPresenceChanged(KWin::AbstractClient*, int); // to be forwarded by Workspace
     void desktopChanged();
+    void activitiesChanged(KWin::AbstractClient* client);
     void x11DesktopIdsChanged();
     void shadeChanged();
     void minimizedChanged();

toplevel.h

@@ -230,7 +230,7 @@ class KWIN_EXPORT Toplevel : public QObject
      */
     Q_PROPERTY(int windowType READ windowType)
 
-    Q_PROPERTY(QStringList activities READ activities NOTIFY activitiesChanged)
+    Q_PROPERTY(QStringList activities READ activities)
 
     /**
      * Whether this Toplevel is managed by KWin (it has control over its placement and other
@@ -608,7 +608,6 @@ Q_SIGNALS:
      * schedule a repaint of the scene.
      */
     void needsRepaint();
-    void activitiesChanged(KWin::Toplevel* toplevel);
     /**
      * Emitted whenever the Toplevel's screen changes. This can happen either in consequence to
      * a screen being removed/added or if the Toplevel's geometry changes.