KEditToolBar: show no-drop cursor with "Available" list for own items

Makes it more obvious to users that items in that list cannot be moved
around there, only dragged out.

src/kedittoolbar.cpp

@@ -18,6 +18,8 @@
 #include <QDialogButtonBox>
 #include <QDir>
 #include <QDomDocument>
+#include <QDragEnterEvent>
+#include <QDragMoveEvent>
 #include <QFile>
 #include <QGridLayout>
 #include <QLabel>
@@ -326,6 +328,25 @@ ToolBarItem *ToolBarListWidget::currentItem() const
     return static_cast<ToolBarItem *>(QListWidget::currentItem());
 }
 
+void ToolBarListWidget::dragEnterEvent(QDragEnterEvent *event)
+{
+    // no internal drag in inactive list
+    if (!m_activeList && (event->source() == this)) {
+        event->ignore();
+        return;
+    }
+    QListWidget::dragEnterEvent(event);
+}
+void ToolBarListWidget::dragMoveEvent(QDragMoveEvent *event)
+{
+    // no internal drag in inactive list
+    if (!m_activeList && (event->source() == this)) {
+        event->ignore();
+        return;
+    }
+    QListWidget::dragMoveEvent(event);
+}
+
 IconTextEditDialog::IconTextEditDialog(QWidget *parent)
     : QDialog(parent)
 {

src/kedittoolbar_p.h

@@ -57,6 +57,8 @@ protected:
 
     bool dropMimeData(int index, const QMimeData *data, Qt::DropAction action) override;
 
+    void dragEnterEvent(QDragEnterEvent *event) override;
+    void dragMoveEvent(QDragMoveEvent *event) override;
     // Skip internal dnd handling in QListWidget ---- how is one supposed to figure this out
     // without reading the QListWidget code !?
     void dropEvent(QDropEvent *ev) override