GN Mac build work

tools/gn/secondary/build/toolchain/mac/BUILD.gn

Index: tools/gn/secondary/build/toolchain/mac/BUILD.gn
diff --git a/tools/gn/secondary/build/toolchain/mac/BUILD.gn b/tools/gn/secondary/build/toolchain/mac/BUILD.gn
index 2752d5a068a03bc6752e790b3d168613606e298a..94131649bd6db6492fe956484c08cecaa05e62ed 100644
--- a/tools/gn/secondary/build/toolchain/mac/BUILD.gn
+++ b/tools/gn/secondary/build/toolchain/mac/BUILD.gn
@@ -2,10 +2,19 @@
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
+# Should only be running on Windows.

[Nico, 2013/10/28 23:05:14]

s/Windows/Mac/

+assert(is_mac)
+
 cc = rebase_path("//third_party/llvm-build/Release+Asserts/bin/clang", ".", root_build_dir)
 cxx = rebase_path("//third_party/llvm-build/Release+Asserts/bin/clang++", ".", root_build_dir)
 ld = cxx
 
+# This will copy the gyp-mac-tool to the build directory. We pass in the source
+# file of the win tool.
+gyp_mac_tool_source =
+  rebase_path("//tools/gyp/pylib/gyp/mac_tool.py", ".", root_build_dir)
+exec_script("setup_toolchain.py", [ gyp_mac_tool_source ], "value")
+
 toolchain("clang") {
   # Make these apply to all tools below.
   lib_prefix = "-l"