GN: Fix use of current_cpu in //build/toolchain/win

build/toolchain/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/sanitizers/sanitizers.gni")
 import("//build/config/win/visual_studio_version.gni")
 import("//build/toolchain/goma.gni")
 import("//build/toolchain/toolchain.gni")
 
 # Should only be running on Windows.
@@ skipping 32 matching lines @@
   exec_script("../../vs_toolchain.py",
               [
                 "copy_dlls",
                 rebase_path(root_build_dir),
                 configuration_name,
                 target_cpu,
               ])
 }
 
 # Parameters:
-#  current_cpu: current_cpu to pass as a build arg
-#  current_os: current_os to pass as a build arg
+#  toolchain_cpu: current_cpu to pass as a build arg
+#  toolchain_os: current_os to pass as a build arg
 #  environment: File name of environment file.
 template("msvc_toolchain") {
   if (defined(invoker.concurrent_links)) {
     concurrent_links = invoker.concurrent_links
   }
 
   env = invoker.environment
 
   cl = invoker.cl
 
@@ skipping 35 matching lines @@
 
     tool("rc") {
       command = "$python_path gyp-win-tool rc-wrapper $env rc.exe {{defines}} {{include_dirs}} /fo{{output}} {{source}}"
       outputs = [
         "$object_subdir/{{source_name_part}}.res",
       ]
       description = "RC {{output}}"
     }
 
     tool("asm") {
-      if (current_cpu == "x64") {
+      if (invoker.toolchain_cpu == "x64") {
         ml = "ml64.exe"
       } else {
         ml = "ml.exe"
       }
       command = "$python_path gyp-win-tool asm-wrapper $env $ml {{defines}} {{include_dirs}} {{asmflags}} /c /Fo{{output}} {{source}}"
       description = "ASM {{output}}"
       outputs = [
         "$object_subdir/{{source_name_part}}.obj",
       ]
     }
@@ skipping 93 matching lines @@
       description = stamp_description
     }
     tool("copy") {
       command = copy_command
       description = copy_description
     }
 
     # When invoking this toolchain not as the default one, these args will be
     # passed to the build. They are ignored when this is the default toolchain.
     toolchain_args() {
-      current_cpu = invoker.current_cpu
+      current_cpu = invoker.toolchain_cpu
+      if (defined(invoker.toolchain_os)) {
+        current_os = invoker.toolchain_os
+      }
       if (defined(invoker.is_clang)) {
         is_clang = invoker.is_clang
       }
-      current_os = invoker.current_os
 
       # This value needs to be passed through unchanged.
       host_toolchain = host_toolchain
     }
   }
 }
 
 # 32-bit toolchains. Only define these when the target architecture is 32-bit
 # since we don't do any 32-bit cross compiles when targeting 64-bit (the
 # build does generate some 64-bit stuff from 32-bit target builds).
 if (target_cpu == "x86") {
   x86_toolchain_data = exec_script("setup_toolchain.py",
                                    [
                                      visual_studio_path,
                                      gyp_win_tool_path,
                                      windows_sdk_path,
                                      visual_studio_runtime_dirs,
                                      "x86",
                                    ],
                                    "scope")
 
   msvc_toolchain("x86") {
     environment = "environment.x86"
-    current_cpu = "x86"
+    toolchain_cpu = "x86"
     cl = "${goma_prefix}\"${x86_toolchain_data.vc_bin_dir}/cl.exe\""
     is_clang = false
   }
 
   msvc_toolchain("clang_x86") {
     environment = "environment.x86"
-    current_cpu = "x86"
+    toolchain_cpu = "x86"
     prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
                          root_build_dir)
     cl = "${goma_prefix}$prefix/clang-cl.exe"
-    current_os = "win"
+    toolchain_os = "win"
     is_clang = true
   }
 }
 
 # 64-bit toolchains.
 x64_toolchain_data = exec_script("setup_toolchain.py",
                                  [
                                    visual_studio_path,
                                    gyp_win_tool_path,
                                    windows_sdk_path,
                                    visual_studio_runtime_dirs,
                                    "x64",
                                  ],
                                  "scope")
 
 msvc_toolchain("x64") {
   environment = "environment.x64"
-  current_cpu = "x64"
+  toolchain_cpu = "x64"
   cl = "${goma_prefix}\"${x64_toolchain_data.vc_bin_dir}/cl.exe\""
   is_clang = false
 }
 
 msvc_toolchain("clang_x64") {
   environment = "environment.x64"
-  current_cpu = "x64"
+  toolchain_cpu = "x64"
   prefix = rebase_path("//third_party/llvm-build/Release+Asserts/bin",
                        root_build_dir)
   cl = "${goma_prefix}$prefix/clang-cl.exe"
-  current_os = "win"
+  toolchain_os = "win"
   is_clang = true
 }
 
 # WinRT toolchains. Only define these when targeting them.
 #
 # NOTE: This is currently broken because it references vc_bin_dir. brettw@
 # changed this around a bit, and I don't know what this should be set to
 # in terms of what setup_toolchain returns for a certain CPU architecture.
 if (target_os == "winrt_81" || target_os == "winrt_81_phone" ||
     target_os == "winrt_10") {
   msvc_toolchain("winrt_x86") {
     environment = "environment.winrt_x86"
     cl = "${goma_prefix}\"${vc_bin_dir}/cl.exe\""
     is_clang = false
 
-    current_cpu = "x86"
-    current_os = current_os
+    toolchain_cpu = "x86"
+    toolchain_os = current_os
   }
 
   msvc_toolchain("winrt_x64") {
     environment = "environment.winrt_x64"
     cl = "${goma_prefix}\"${vc_bin_dir}/cl.exe\""
     is_clang = false
 
-    current_cpu = "x64"
-    current_os = current_os
+    toolchain_cpu = "x64"
+    toolchain_os = current_os
   }
 }