DockWidget: decouple more from QtWidgets

src/View.cpp

@@ -17,6 +17,7 @@
 #include "controllers/Stack.h"
 #include "controllers/TitleBar.h"
 #include "controllers/TabBar.h"
+#include "controllers/MainWindow.h"
 
 #include <QWidget> // TODOv2 remove
 
@@ -229,6 +230,14 @@ Controllers::DockWidget *View::asDockWidgetController() const
     return nullptr;
 }
 
+Controllers::MainWindow *View::asMainWindowController() const
+{
+    if (m_controller && m_controller->is(Type::MainWindow))
+        return qobject_cast<Controllers::MainWindow *>(m_controller);
+
+    return nullptr;
+}
+
 bool View::equals(const View *other) const
 {
     return other && handle() == other->handle();