Don't allow tearoff under Wayland

as floating toolbars aren't movable there.

Change-Id: I543344946f02d5a336ff738b4d6d9f9b21c595e9
Reviewed-on: https://gerrit.libreoffice.org/48096Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Maxim Monastirsky <momonasmon@gmail.com>

vcl/source/window/dockmgr.cxx

@@ -799,7 +799,8 @@ void ImplDockingWindowWrapper::StartPopupMode( ToolBox *pParentToolBox, FloatWin
     ImplPreparePopupMode();
 
     // don't allow tearoff, if globally disabled
-    if( GetWindow()->GetType() == WindowType::TOOLBOX && ToolBox::AlwaysLocked() )
+    if( !StyleSettings::GetDockingFloatsSupported() ||
+        ( GetWindow()->GetType() == WindowType::TOOLBOX && ToolBox::AlwaysLocked() ) )
         nFlags &= ~FloatWinPopupFlags::AllowTearOff;
 
     // if the subtoolbar was opened via keyboard make sure that key events