Re-enable several MSVC warnings

core/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 "core/fpdfapi/fpdf_page/pageint.h"
 
 #include <algorithm>
 
@@ skipping 695 matching lines @@
 void CPDF_Page::GetDisplayMatrix(CFX_Matrix& matrix,
                                  int xPos,
                                  int yPos,
                                  int xSize,
                                  int ySize,
                                  int iRotate) const {
   if (m_PageWidth == 0 || m_PageHeight == 0) {
     return;
   }
   CFX_Matrix display_matrix;
-  int x0, y0, x1, y1, x2, y2;
+  int x0 = 0;
+  int y0 = 0;
+  int x1 = 0;
+  int y1 = 0;
+  int x2 = 0;
+  int y2 = 0;
   iRotate %= 4;
   switch (iRotate) {
     case 0:
       x0 = xPos;
       y0 = yPos + ySize;
       x1 = xPos;
       y1 = yPos;
       x2 = xPos + xSize;
       y2 = yPos + ySize;
       break;
@@ skipping 29 matching lines @@
   matrix = m_PageMatrix;
   matrix.Concat(display_matrix);
 }
 
 CPDF_ParseOptions::CPDF_ParseOptions() {
   m_bTextOnly = FALSE;
   m_bMarkedContent = TRUE;
   m_bSeparateForm = TRUE;
   m_bDecodeInlineImage = FALSE;
 }