QML DropArea does not update mouse cursor shape correctly

When holding a dragged item over a QML DropArea it shows the action it will perform by changing the mouse cursor to DragCopyCursor, DragMoveCursor or DragLinkCursor, depending on which modifier keys are held at the same time.

However, the cursor does not update directly when pressing or releasing a modifer key.

For the cursor to update the user first has to move the cursor outside the DropArea, and then move the cursor back in.

This is inconsistent with how drag-and-drop works in QWidgets and with the system in general, the cursor is supposed to update whenever a modifier key is pressed or released so that it is clear to the user which action will be performed.

Tested with the "externaldraganddrop" example.