Add icon property and changed signal to KDecoration

Replaces the pure virtual method which the Decoration had to
implement. Instead the Decoration can now connect to the signal.

For KCommonDecoration there is no change at all except that the
invoked method is turned into a slot.

client.cpp

@@ -428,6 +428,7 @@ void Client::createDecoration(const QRect& oldgeom)
     } else {
         decoration = decorationPlugin()->createDecoration(bridge);
     }
+    connect(this, &Client::iconChanged, decoration, &KDecoration::iconChanged);
     connect(this, &Client::shadeChanged, decoration, &KDecoration::shadeChanged);
     connect(this, &Client::desktopChanged, decoration, &KDecoration::desktopChanged);
     connect(this, &Client::captionChanged, decoration, &KDecoration::captionChanged);

clients/aurorae/src/aurorae.cpp

@@ -306,11 +306,6 @@ bool AuroraeClient::eventFilter(QObject *object, QEvent *event)
     return false;
 }
 
-void AuroraeClient::iconChange()
-{
-    emit iconChanged();
-}
-
 void AuroraeClient::maximizeChange()
 {
     emit maximizeChanged();

clients/aurorae/src/aurorae.h

@@ -89,7 +89,6 @@ class AuroraeClient : public KDecoration
     Q_OBJECT
     Q_PROPERTY(QRect geometry READ geometry)
     Q_PROPERTY(int height READ height)
-    Q_PROPERTY(QIcon icon READ icon NOTIFY iconChanged)
     Q_PROPERTY(bool closeable READ isCloseable CONSTANT)
     Q_PROPERTY(bool maximizeable READ isMaximizable CONSTANT)
     Q_PROPERTY(bool minimizeable READ isMinimizable CONSTANT)
@@ -114,7 +113,6 @@ public:
     virtual ~AuroraeClient();
     virtual bool eventFilter(QObject *object, QEvent *event);
     virtual void borders(int& left, int& right, int& top, int& bottom) const;
-    virtual void iconChange();
     virtual void init();
     virtual void maximizeChange();
     virtual QSize minimumSize() const;
@@ -130,7 +128,6 @@ public:
     Q_INVOKABLE QVariant readConfig(const QString &key, const QVariant &defaultValue = QVariant());
 
 Q_SIGNALS:
-    void iconChanged();
     void maximizeChanged();
     void keepAboveChangedWrapper();
     void keepBelowChangedWrapper();

libkdecorations/kcommondecoration.cpp

@@ -61,6 +61,7 @@ KCommonDecoration::KCommonDecoration(KDecorationBridge* bridge, KDecorationFacto
     connect(wrapper, &KDecoration::captionChanged, this, &KCommonDecoration::captionChange);
     connect(wrapper, &KDecoration::desktopChanged, this, &KCommonDecoration::desktopChange);
     connect(wrapper, &KDecoration::shadeChanged, this, &KCommonDecoration::shadeChange);
+    connect(wrapper, &KDecoration::iconChanged, this, &KCommonDecoration::iconChange);
 }
 
 KCommonDecoration::~KCommonDecoration()

libkdecorations/kcommondecoration.h

@@ -257,12 +257,12 @@ public:
     virtual void resize(const QSize& s);
     virtual QSize minimumSize() const;
     virtual void maximizeChange();
-    virtual void iconChange();
 public Q_SLOTS:
     virtual void activeChange();
     virtual void captionChange();
     virtual void desktopChange();
     virtual void shadeChange();
+    virtual void iconChange();
     void keepAboveChange(bool above);
     void keepBelowChange(bool below);
     void slotMaximize();

libkdecorations/kcommondecoration_p.cpp

@@ -68,11 +68,6 @@ QSize KCommonDecorationWrapper::minimumSize() const
     return decoration->minimumSize();
 }
 
-void KCommonDecorationWrapper::iconChange()
-{
-    return decoration->iconChange();
-}
-
 void KCommonDecorationWrapper::maximizeChange()
 {
     return decoration->maximizeChange();

libkdecorations/kcommondecoration_p.h

@@ -49,7 +49,6 @@ public:
     virtual void borders(int& left, int& right, int& top, int& bottom) const;
     virtual void resize(const QSize& s);
     virtual QSize minimumSize() const;
-    virtual void iconChange();
     virtual void maximizeChange();
     virtual bool drawbound(const QRect& geom, bool clear);
     virtual bool windowDocked(Position side);

libkdecorations/kdecoration.h

@@ -495,6 +495,7 @@ class KWIN_EXPORT KDecoration
     Q_PROPERTY(int desktop READ desktop WRITE setDesktop NOTIFY desktopChanged)
     Q_PROPERTY(bool onAllDesktops READ isOnAllDesktops NOTIFY desktopChanged)
     Q_PROPERTY(bool setShade READ isSetShade NOTIFY shadeChanged)
+    Q_PROPERTY(QIcon icon READ icon NOTIFY iconChanged)
 public:
     /**
      * Constructs a KDecoration object. Both the arguments are passed from
@@ -819,10 +820,6 @@ public:
     virtual QSize minimumSize() const = 0;
 
 public Q_SLOTS:
-    /**
-     * This function is called whenever the window icon changes. Use icon() to get it.
-     */
-    virtual void iconChange() = 0;
     /**
      * This function is called whenever the maximalization state of the window changes.
      * Use maximizeMode() to get the current state.
@@ -850,6 +847,10 @@ Q_SIGNALS:
      * isShade() to get the current state.
      */
     void shadeChanged();
+    /**
+     * This signal is emitted whenever the window icon changes. Use icon() to get it.
+     */
+    void iconChanged();
     /**
      * This signal is emitted whenever the window's keep-above state changes.
      */