Resolve macro redefinition warnings when built in Chromium

third_party/BUILD.gn

 # 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.
 
 import("../pdfium.gni")
 
 group("third_party") {
   deps = [
     ":bigint",
     ":fx_freetype",
@@ skipping 310 matching lines @@
     "libpng16/pngstruct.h",
     "libpng16/pngtrans.c",
     "libpng16/pngwio.c",
     "libpng16/pngwrite.c",
     "libpng16/pngwtran.c",
     "libpng16/pngwutil.c",
   ]
 }
 
 if (pdf_enable_xfa) {
+  config("fx_tiff_warnings") {
+    visibility = [ ":*" ]
+    if (is_win) {
+      cflags = [
+        "/wd4005",  # Macro redefinition for 'WIN32_LEAN_AND_MEAN'.
+      ]
+    }
+  }
   source_set("fx_tiff") {
     configs -= [ "//build/config/compiler:chromium_code" ]
     configs += [
       "//build/config/compiler:no_chromium_code",
       "../:pdfium_config",
+
+      ":fx_tiff_warnings",
     ]
     deps = [
       "//third_party:jpeg",
     ]
     sources = [
       "libtiff/tif_aux.c",
       "libtiff/tif_close.c",
       "libtiff/tif_codec.c",
       "libtiff/tif_color.c",
       "libtiff/tif_compress.c",
@@ skipping 78 matching lines @@
   sources = [
     "base/logging.h",
     "base/macros.h",
     "base/numerics/safe_conversions.h",
     "base/numerics/safe_conversions_impl.h",
     "base/numerics/safe_math.h",
     "base/numerics/safe_math_impl.h",
     "base/stl_util.h",
   ]
 }