Audit GN cflags and defines to match GYP build.

build/config/win/BUILD.gn

 # Copyright (c) 2013 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.
 
 import("//build/config/win/visual_studio_version.gni")
 
 # Compiler setup for the Windows SDK. Applied to all targets.
 config("sdk") {
   # The include path is the stuff returned by the script.
   #include_dirs = msvc_config[0]  TODO(brettw) make this work.
 
   defines = [
     "_ATL_NO_OPENGL",
     "_WINDOWS",
     "CERT_CHAIN_PARA_HAS_EXTRA_FIELDS",
     "NTDDI_VERSION=0x06030000",
     "PSAPI_VERSION=1",
     "WIN32",
     "_SECURE_ATL",
+
+    # This is required for ATL to use XP-safe versions of its functions.
+    "_USING_V110_SDK71_",
   ]
 }
 
 # Sets the default Windows build version. This is separated because some
 # targets need to manually override it for their compiles.
 config("winver") {
   defines = [
     "_WIN32_WINNT=0x0603",
     "WINVER=0x0603",
   ]
@@ skipping 101 matching lines @@
 
 # Nominmax --------------------------------------------------------------------
 
 # Some third party code defines NOMINMAX before including windows.h, which
 # then causes warnings when it's been previously defined on the command line.
 # For such targets, this config can be removed.
 
 config("nominmax") {
   defines = [ "NOMINMAX" ]
 }