Fix regression in AUI floating pane positioning when dragging

Fix position updating broken since the recent changes of e777a82bfd (Fix
AUI floating position mismatch, 2022-05-25).

Closes #22533.

(cherry picked from commit 0e57ed18518d0417759346541dd3c60e1f3e5e8e)

docs/changes.txt

@@ -239,6 +239,7 @@ All (GUI):
 
 - Fix grid window scrollbars when freezing part of the grid (#22602).
 - Avoid warnings with wxStaticText flags in C++20 (David Connet, #22656).
+- Fix AUI floating pane position when dragging (Konstantin S. Matveyev, #22533).
 
 wxGTK:
 

src/aui/floatpane.cpp

@@ -207,7 +207,7 @@ void wxAuiFloatingFrame::OnMoveEvent(wxMoveEvent& event)
     if (m_ownerMgr)
     {
         m_ownerMgr->GetPane(m_paneWindow).
-            floating_pos = event.GetPosition();
+            floating_pos = GetRect().GetPosition();
     }
 
     if (!m_solidDrag)