Allow any window to be bounds-checked (#4802)

Co-authored-by: Rasmus Karlsson <rasmus.karlsson@pajlada.com>

src/widgets/splits/SplitHeader.cpp

@@ -956,7 +956,7 @@ void SplitHeader::enterEvent(QEvent *event)
         auto pos = this->mapToGlobal(this->rect().bottomLeft()) +
                    QPoint((this->width() - tooltip->width()) / 2, 1);
 
-        tooltip->moveTo(pos, BaseWindow::BoundsChecker::CursorPosition);
+        tooltip->moveTo(pos, widgets::BoundsChecking::CursorPosition);
         tooltip->show();
     }