Improves GN's make_global_settings

build/toolchain/android/BUILD.gn

 # Copyright 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/android/config.gni")
 import("//build/toolchain/clang.gni")
 import("//build/toolchain/goma.gni")
 import("//build/toolchain/gcc_toolchain.gni")
 
 # Get the Android version of the name of the build host's architecture.
 if (build_cpu_arch == "x64") {
   android_host_arch = "x86_64"
 } else if (build_cpu_arch == "x86") {
   android_host_arch = "x86"
 } else {
   assert(false, "Need Android toolchain support for your build OS.")
 }
 
 if (is_gyp) {
   # Set the compilers for GYP to use. This logic is only relevant to GYP where
   # there is "a" target compiler. In native GN builds, we have separate
   # compilers for the toolchains below, any or all of which could be active in
   # any given build.
   if (is_clang) {
     # Set the GYP header for all toolchains when running under Clang.
-    gyp_header = make_clang_global_settings
+    make_global_settings = make_clang_global_settings
   } else {
     # Find the compiler for GYP for non-Clang Android.
     if (cpu_arch == "x86") {
       android_toolchain_arch = "x86-4.6"
     } else if (cpu_arch == "arm") {
       android_toolchain_arch = "arm-linux-androideabi-4.6"
     } else if (cpu_arch == "mipsel") {
       android_toolchain_arch = "mipsel-linux-android-4.6"
     } else {
       assert(false, "Need Android toolchain support for your platform.")
     }
 
     # The extra slash before "toolchains" is because GYP generates this and we
     # have to match the make_global_settings character-for-character,
     # TODO(brettw) remove extra slash before toolchains when GYP compat is no
     # longer necessary.
     android_toolchain =
       "$android_ndk_root//toolchains/$android_toolchain_arch/prebuilt/$build_os-$android_host_arch/bin"
 
     # This script will find the compilers for the given Android toolchain
     # directory.
     android_compilers = exec_script("find_android_compiler.py",
                                     [android_toolchain], "value")
-    gyp_header =
-      "'make_global_settings': [" +
+    make_global_settings =
       "['CC', '" + android_compilers[0] + "']," +
       "['CXX', '" + android_compilers[1] + "']," +
       "['CC.host', '" + android_compilers[2] + "']," +
-      "['CXX.host', '" + android_compilers[3] + "']," +
-      "],"
+      "['CXX.host', '" + android_compilers[3] + "'],"
   }
 
   if (use_goma) {
     # There is a TODO(yyanagisawa) in common.gypi about the make generator not
     # supporting CC_wrapper without CC. As a result, we must add a condition
     # when on the generator when we're not explicitly setting the variables
     # above (which happens when gyp_header is empty at this point).
     #
     # GYP will interpret the file once for each generator, so we have to write
     # this condition into the GYP file since the user could have more than one
     # generator set.
-    if (gyp_header == "") {
-      gyp_header +=
-        "'conditions':" +
-        "['\"<(GENERATOR)\"==\"ninja\"', {" +
-        make_goma_global_settings +
-        "}],"
-    } else {
-      gyp_header += make_goma_global_settings
-    }
+    gyp_header =
+      "'conditions': [" +
+      "['\"<(GENERATOR)\"==\"ninja\"', { 'make_global_settings': [" +
+      make_global_settings +
+      make_goma_global_settings +
+      "]}]],"
+  } else {
+    gyp_header = "'make_global_settings': [" + make_global_settings + "],"
   }
 }
 
 gcc_toolchain("x86") {
   prefix = "$android_ndk_root/toolchains/x86-4.6/prebuilt/$build_os-$android_host_arch/bin/i686-linux-android-"
   cc  = prefix + "gcc"
   cxx = prefix + "g++"
   ar  = prefix + "ar"
   ld  = cxx
 
@@ skipping 15 matching lines @@
 gcc_toolchain("mipsel") {
   prefix = "$android_ndk_root/toolchains/mipsel-linux-android-4.6/prebuilt/$build_os-$android_host_arch/bin/mipsel-linux-android-"
   cc  = prefix + "gcc"
   cxx = prefix + "g++"
   ar  = prefix + "ar"
   ld  = cxx
 
   toolchain_cpu_arch = "mipsel"
   toolchain_os = "android"
 }