ccrystaltextview.cpp: Fix crash at preview when the printer is not installed. (I discovered this when I ran WinMerge on Wine.)

Author: sdottaka

Externals/crystaledit/editlib/ccrystaltextview.cpp

@@ -596,6 +596,7 @@ CCrystalTextView::CCrystalTextView ()
 , m_bIncrementalFound(false)
 , m_rxmatch{}
 , m_nRenderingMode(s_nRenderingModeDefault)
+, m_pCrystalRendererSaved(nullptr)
 {
 #ifdef _WIN64
   if (m_nRenderingMode == RENDERING_MODE_GDI)
@@ -3004,8 +3005,11 @@ OnBeginPrinting (CDC * pdc, CPrintInfo * pInfo)
 void CCrystalTextView::
 OnEndPrinting (CDC * pdc, CPrintInfo * pInfo)
 {
-  m_pCrystalRenderer.reset(m_pCrystalRendererSaved);
-
+  if (m_pCrystalRendererSaved)
+  {
+    m_pCrystalRenderer.reset(m_pCrystalRendererSaved);
+    m_pCrystalRendererSaved = nullptr;
+  }
   if (m_pPrintFont != nullptr)
     {
       delete m_pPrintFont;