Disable pointer-to-int conversion warning.

BUILD.gn

 # Copyright 2014 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 pdf_use_skia = false
 
 config("pdfium_config") {
   cflags = []
   defines = [
     "FOXIT_CHROME_BUILD",
@@ skipping 456 matching lines @@
     "core/src/fxcodec/libjpeg/jpegint.h",
     "core/src/fxcodec/libjpeg/jpeglib.h",
     "core/src/fxcodec/libjpeg/jversion.h",
     "core/src/fxcodec/libjpeg/makefile",
     "core/src/fxcodec/libjpeg/transupp.h",
   ]
   configs -= [ "//build/config/compiler:chromium_code" ]
   if (is_posix) {
     configs -= [ "//build/config/gcc:no_exceptions" ]
   }
+
+  if (is_posix) {
+    # core/src/fxcodec/fx_libopenjpeg/src/fx_mct.c does an pointer-to-int
+    # conversion to check that an address is 16-bit aligned (benign).
+    cflags_c = [ "-Wno-pointer-to-int-cast" ]
+  }
   configs += [ ":pdfium_config", "//build/config/compiler:no_chromium_code" ]
 }
 
 static_library("fxcrt") {
   sources = [
     "core/include/fxcrt/fx_arb.h",
     "core/include/fxcrt/fx_basic.h",
     "core/include/fxcrt/fx_coordinates.h",
     "core/include/fxcrt/fx_ext.h",
     "core/include/fxcrt/fx_memory.h",
@@ skipping 352 matching lines @@
     "fpdfsdk/src/formfiller/FFL_RadioButton.cpp",
     "fpdfsdk/src/formfiller/FFL_TextField.cpp",
     "fpdfsdk/src/formfiller/FFL_Utils.cpp",
   ]
   configs -= [ "//build/config/compiler:chromium_code" ]
   if (is_posix) {
     configs -= [ "//build/config/gcc:no_exceptions" ]
   }
   configs += [ ":pdfium_config", "//build/config/compiler:no_chromium_code" ]
 }