tdf#113548: another case of crash in GrabFocus during dispose

Change-Id: I70776b80f70985a122e28854177c6d0c43839d65
Reviewed-on: https://gerrit.libreoffice.org/44113Reviewed-by: Aron Budea <aron.budea@collabora.com>
Tested-by: Aron Budea <aron.budea@collabora.com>

sw/source/uibase/docvw/srcedtw.cxx

@@ -793,7 +793,8 @@ void SwSrcEditWindow::HandleWheelCommand( const CommandEvent& rCEvt )
 
 void SwSrcEditWindow::GetFocus()
 {
-    m_pOutWin->GrabFocus();
+    if (m_pOutWin)
+        m_pOutWin->GrabFocus();
 }
 
 static bool lcl_GetLanguagesForEncoding(rtl_TextEncoding eEnc, LanguageType aLanguages[])