Make goma work on win GN builds.

build/vs_toolchain.py

Index: build/vs_toolchain.py
diff --git a/build/vs_toolchain.py b/build/vs_toolchain.py
index fb7e142e0e783fc0f0a971bd138d95f5f9fcec09..870c1290cce52fc1b4c153eff1a41301d1b9ad1a 100644
--- a/build/vs_toolchain.py
+++ b/build/vs_toolchain.py
@@ -181,7 +181,7 @@ def Update():
   return 0
 
 
-def GetToolchainDir():
+def GetToolchainDir(cpu_arch):
   """Gets location information about the current toolchain (must have been
   previously updated by 'update'). This is used for the GN build."""
   runtime_dll_dirs = SetEnvironmentAndGetRuntimeDllDirs()
@@ -192,17 +192,30 @@ def GetToolchainDir():
     if os.path.isdir(default_sdk_path):
       os.environ['WINDOWSSDKDIR'] = default_sdk_path
 
+  # We only support the 64-bit toolchains, but we need to point
+  # GN to either the 32-bit-generating one or the 64-bit-generating one.
+  assert(cpu_arch in ("x86", "x64"))
+  if cpu_arch == 'x86':
+    vc_bin_subdir = 'amd64_x86'

[scottmg, 2014/11/21 02:35:41]

this was what i didn't really want; the toolchain has already set up the paths,
so I think finding it there better.

[Dirk Pranke, 2014/11/21 02:46:00]

Okay, I think I understand the concerns now. I will take another look.

+  else:
+    vc_bin_subdir = 'amd64'
+
+  vs_path = os.environ['GYP_MSVS_OVERRIDE_PATH']

[scottmg, 2014/11/21 02:35:41]

gyp_msvs_override_path won't be set on the non-depot_tools path. there's going
to be need to be a registry search in setup_toolchain for that, so it would be
good to communicate the information from there rather than re-find it.

[Dirk Pranke, 2014/11/21 02:46:00]

Ack.

+  vc_bin_dir = os.path.join(vs_path, 'VC', 'bin', vc_bin_subdir)
+
   print '''vs_path = "%s"
 sdk_path = "%s"
 vs_version = "%s"
 wdk_dir = "%s"
 runtime_dirs = "%s"
+vc_bin_dir = "%s"
 ''' % (
-      os.environ['GYP_MSVS_OVERRIDE_PATH'],
+      vs_path,
       os.environ['WINDOWSSDKDIR'],
       os.environ['GYP_MSVS_VERSION'],
       os.environ.get('WDK_DIR', ''),
-      ';'.join(runtime_dll_dirs))
+      ';'.join(runtime_dll_dirs),
+     vc_bin_dir)
 
 
 def main():