Remove "nacl_defines" from the GN build.

components/nacl/nacl_defines.gni

Index: components/nacl/nacl_defines.gni
diff --git a/components/nacl/nacl_defines.gni b/components/nacl/nacl_defines.gni
deleted file mode 100644
index 8d69b16af971934df3c4b617bc769e431d670368..0000000000000000000000000000000000000000
--- a/components/nacl/nacl_defines.gni
+++ /dev/null
@@ -1,58 +0,0 @@
-# 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.
-
-nacl_defines = []
-if (is_win) {
-  nacl_defines += [
-    "NACL_WINDOWS=1",
-    "NACL_LINUX=0",
-    "NACL_OSX=0",
-    "NACL_ANDROID=0",
-  ]
-} else if (is_linux) {
-  nacl_defines += [
-    "NACL_WINDOWS=0",
-    "NACL_LINUX=1",
-    "NACL_OSX=0",
-    "NACL_ANDROID=0",
-  ]
-} else if (is_mac) {
-  nacl_defines += [
-    "NACL_WINDOWS=0",
-    "NACL_LINUX=0",
-    "NACL_OSX=1",
-    "NACL_ANDROID=0",
-  ]
-}
-
-if (is_android) {
-  nacl_defines += [
-    "NACL_WINDOWS=0",
-    "NACL_LINUX=1",
-    "NACL_OSX=0",
-    "NACL_ANDROID=1",
-  ]
-}
-
-if (cpu_arch == "x86") {
-  nacl_defines += [
-    "NACL_BUILD_SUBARCH=32",
-    "NACL_BUILD_ARCH=x86",
-  ]
-} else if (cpu_arch == "x64") {
-  nacl_defines += [
-    "NACL_BUILD_SUBARCH=64",
-    "NACL_BUILD_ARCH=x86",
-  ]
-} else if (cpu_arch == "arm") {
-  nacl_defines += [
-    "NACL_BUILD_ARCH=arm",
-    "NACL_BUILD_SUBARCH=32",
-  ]
-} else if (cpu_arch == "mipsel") {
-  nacl_defines += [
-    "NACL_BUILD_ARCH=mips",
-    "NACL_BUILD_SUBARCH=32",
-  ]
-}