Fix partial information printed with blank window covering the center

core/src/fpdfapi/fpdf_page/fpdf_page.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "pageint.h"
 
 #include "core/include/fpdfapi/fpdf_module.h"
 #include "core/include/fpdfapi/fpdf_page.h"
@@ skipping 657 matching lines @@
 }
 CPDF_PageObjects::CPDF_PageObjects(FX_BOOL bReleaseMembers)
     : m_pFormDict(nullptr),
       m_pFormStream(nullptr),
       m_pDocument(nullptr),
       m_pPageResources(nullptr),
       m_pResources(nullptr),
       m_Transparency(0),
       m_ObjectList(128),
       m_bBackgroundAlphaNeeded(FALSE),
+      m_bHasImageMask(FALSE),
       m_bReleaseMembers(bReleaseMembers),
       m_pParser(nullptr),
       m_ParseState(CONTENT_NOT_PARSED) {}
 CPDF_PageObjects::~CPDF_PageObjects() {
   delete m_pParser;
   if (!m_bReleaseMembers) {
     return;
   }
   FX_POSITION pos = m_ObjectList.GetHeadPosition();
   while (pos) {
@@ skipping 315 matching lines @@
                      (FX_FLOAT)y0);
   matrix = m_PageMatrix;
   matrix.Concat(display_matrix);
 }
 CPDF_ParseOptions::CPDF_ParseOptions() {
   m_bTextOnly = FALSE;
   m_bMarkedContent = TRUE;
   m_bSeparateForm = TRUE;
   m_bDecodeInlineImage = FALSE;
 }