Add a generic interface for the classic indicator window

this removes QWidget references from ClassicIndicators.cpp.
Both the QtQuick and QtWidgets impl will implement this new
interface, which is what ClassicIndicators.cpp uses now

src/qtwidgets/views/ClassicIndicatorsWindow_qtwidgets.cpp

@@ -269,6 +269,37 @@ void IndicatorWindow_qtwidgets::updatePositions()
     }
 }
 
+void IndicatorWindow_qtwidgets::raise()
+{
+    QWidget::raise();
+}
+
+void IndicatorWindow_qtwidgets::setGeometry(QRect rect)
+{
+    QWidget::setGeometry(rect);
+}
+
+void IndicatorWindow_qtwidgets::setObjectName(const QString &name)
+{
+    QWidget::setObjectName(name);
+}
+
+void IndicatorWindow_qtwidgets::setVisible(bool is)
+{
+    QWidget::setVisible(is);
+}
+
+void IndicatorWindow_qtwidgets::resize(QSize size)
+{
+    QWidget::resize(size);
+}
+
+bool IndicatorWindow_qtwidgets::isWindow() const
+{
+    /// TODOv2
+    return KDDockWidgets::isWindow(this);
+}
+
 Indicator::Indicator(ClassicIndicators *classicIndicators, IndicatorWindow_qtwidgets *parent, DropLocation location)
     : QWidget(parent)
     , q(classicIndicators)