Linux: Fixed a DragAndDrop issue between different containers

modules/juce_gui_basics/mouse/juce_DragAndDropContainer.cpp

@@ -243,13 +243,34 @@ private:
         return dynamic_cast<DragAndDropTarget*> (currentlyOverComp.get());
     }
 
+    static Component* findDesktopComponentBelow (Point<int> screenPos)
+    {
+        auto& desktop = Desktop::getInstance();
+
+        for (auto i = desktop.getNumComponents(); --i >= 0;)
+        {
+            auto* desktopComponent = desktop.getComponent (i);
+            auto dPoint = desktopComponent->getLocalPoint (nullptr, screenPos);
+
+            if (auto* c = desktopComponent->getComponentAt (dPoint))
+            {
+                auto cPoint = c->getLocalPoint (desktopComponent, dPoint);
+
+                if (c->hitTest (cPoint.getX(), cPoint.getY()))
+                    return c;
+            }
+        }
+
+        return nullptr;
+    }
+
     DragAndDropTarget* findTarget (Point<int> screenPos, Point<int>& relativePos,
                                    Component*& resultComponent) const
     {
         auto* hit = getParentComponent();
 
         if (hit == nullptr)
-            hit = Desktop::getInstance().findComponentAt (screenPos);
+            hit = findDesktopComponentBelow (screenPos);
         else
             hit = hit->getComponentAt (hit->getLocalPoint (nullptr, screenPos));