Re-enable warning 4701 for GN build and some cleanup

core/fpdfapi/fpdf_render/fpdf_render_pattern.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_render/render_int.h"
 
 #include "core/fpdfapi/fpdf_page/cpdf_graphicstates.h"
 #include "core/fpdfapi/fpdf_page/cpdf_meshstream.h"
@@ skipping 635 matching lines @@
             int y_scale,
             int left,
             int bottom,
             Coon_Bezier C1,
             Coon_Bezier C2,
             Coon_Bezier D1,
             Coon_Bezier D2) {
     FX_BOOL bSmall = C1.Distance() < 2 && C2.Distance() < 2 &&
                      D1.Distance() < 2 && D2.Distance() < 2;
     Coon_Color div_colors[4];
-    int d_bottom, d_left, d_top, d_right;
+    int d_bottom = 0;
+    int d_left = 0;
+    int d_top = 0;
+    int d_right = 0;
     div_colors[0].BiInterpol(patch_colors, left, bottom, x_scale, y_scale);
     if (!bSmall) {
       div_colors[1].BiInterpol(patch_colors, left, bottom + 1, x_scale,
                                y_scale);
       div_colors[2].BiInterpol(patch_colors, left + 1, bottom + 1, x_scale,
                                y_scale);
       div_colors[3].BiInterpol(patch_colors, left + 1, bottom, x_scale,
                                y_scale);
       d_bottom = div_colors[3].Distance(div_colors[0]);
       d_left = div_colors[1].Distance(div_colors[0]);
@@ skipping 540 matching lines @@
     }
   }
   if (bStroke) {
     CPDF_Color& StrokeColor = *pPathObj->m_ColorState.GetStrokeColor();
     if (StrokeColor.m_pCS && StrokeColor.m_pCS->GetFamily() == PDFCS_PATTERN) {
       DrawPathWithPattern(pPathObj, pObj2Device, &StrokeColor, TRUE);
       bStroke = FALSE;
     }
   }
 }