Resolves: tdf#121641 properties invisible after 'reset'

Change-Id: Iedb2b11be0e008501273925d6ae7137b28c3b912
Reviewed-on: https://gerrit.libreoffice.org/64539
Tested-by: Jenkins
Tested-by: Xisco Faulí <xiscofauli@libreoffice.org>
Reviewed-by: Markus Mohrhard <markus.mohrhard@googlemail.com>
(cherry picked from commit 01e263ba)

sfx2/source/dialog/dinfdlg.cxx

@@ -1553,7 +1553,14 @@ void CustomPropertiesWindow::dispose()
 {
     m_aEditLoseFocusIdle.Stop();
     m_aBoxLoseFocusIdle.Stop();
-    ClearAllLines();
+
+    for (CustomPropertyLine* pLine : m_aCustomPropertiesLines)
+    {
+        delete pLine;
+    }
+    m_pCurrentLine = nullptr;
+    m_aCustomPropertiesLines.clear();
+
     m_pHeaderBar.clear();
     m_pScrollBar.clear();
     m_pHeaderAccName.clear();
@@ -1786,15 +1793,11 @@ bool CustomPropertiesWindow::AreAllLinesValid() const
 
 void CustomPropertiesWindow::ClearAllLines()
 {
-    std::vector< CustomPropertyLine* >::iterator pIter;
-    for ( pIter = m_aCustomPropertiesLines.begin();
-          pIter != m_aCustomPropertiesLines.end(); ++pIter )
+    for (CustomPropertyLine* pLine : m_aCustomPropertiesLines)
     {
-        CustomPropertyLine* pLine = *pIter;
-        delete pLine;
+        pLine->Clear();
     }
     m_aCustomProperties.clear();
-    m_aCustomPropertiesLines.clear();
     m_nScrollPos = 0;
 }