tdf#118549 crash on dialog teardown

only an issue for the current partially complete interim case

Change-Id: Iaf1ef4dabca1cdd5d2d90028edf5793cf45feb20
Reviewed-on: https://gerrit.libreoffice.org/57501
Tested-by: Jenkins
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

cui/source/tabpages/tpcolor.cxx

@@ -166,7 +166,9 @@ SvxColorTabPage::~SvxColorTabPage()
 void SvxColorTabPage::dispose()
 {
     mpTopDlg.clear();
+    m_xValSetRecentListWin.reset();
     m_xValSetRecentList.reset();
+    m_xValSetColorListWin.reset();
     m_xValSetColorList.reset();
     SfxTabPage::dispose();
 }