Renamed signal to windowActiveAboutToChange()

Added the 'aboutTo', as the event hasn't been caught by the top-level
window yet

Changelog

@@ -5,7 +5,7 @@
   - Wayland support
   - Added Flag_KeepAboveIfNotUtilityWindow, so you can have keep above even if
     floating window is shown in the task-bar.
-  - Added DockWidget::windowActiveChanged() signal
+  - Added DockWidget::windowActiveAboutToChange() signal
 
 * v1.1.0 (26 October 2020)
   - New drop indicator style type: Segmented Indicators

src/DockWidgetBase.cpp

@@ -602,7 +602,7 @@ bool DockWidgetBase::eventFilter(QObject *watched, QEvent *event)
     const bool isWindowActivate = event->type() == QEvent::WindowActivate;
     const bool isWindowDeactivate = event->type() == QEvent::WindowDeactivate;
     if (isWindowActivate || isWindowDeactivate)
-        Q_EMIT windowActiveChanged(isWindowActivate);
+        Q_EMIT windowActiveAboutToChange(isWindowActivate);
 
     return QWidgetAdapter::eventFilter(watched, event);
 }

src/DockWidgetBase.h

@@ -410,7 +410,10 @@ Q_SIGNALS:
     ///@brief Emitted when the top-level window this dock widget is in is activated or deactivated
     ///This is convenience to replace tracking dockWidget->window(), since the window changes when
     ///docking and undocking
-    void windowActiveChanged(bool activated);
+    ///
+    /// It's called 'aboutTo' because it's done in an event filter and the target window doesn't
+    /// have it's 'activeWindow' property updated yet at this point.
+    void windowActiveAboutToChange(bool activated);
 
 protected:
     void onParentChanged();