Fix GN generation for WinASAN build

courgette/BUILD.gn

Index: courgette/BUILD.gn
diff --git a/courgette/BUILD.gn b/courgette/BUILD.gn
index f80206cf7db019a0341e72dc3a9164aee4d50d1c..03fb5fc74ab4e61d147730932e1846cd8b2cc0aa 100644
--- a/courgette/BUILD.gn
+++ b/courgette/BUILD.gn
@@ -134,7 +134,13 @@ if (!is_ios) {
       # Make sure that we have a copy of courgette64.exe in the root out
       # directory.
       copy("copy_courgette_binaries") {
-        courgette64_label = ":courgette(//build/toolchain/win:x64)"
+        if (is_clang) {
+          courgette64_toolchain = "//build/toolchain/win:clang_x64"
+        } else {
+          courgette64_toolchain = "//build/toolchain/win:x64"
+        }
+        courgette64_label = ":courgette($courgette64_toolchain)"
+
         courgette64_out_dir = get_label_info(courgette64_label, "root_out_dir")
         sources = [
           "$courgette64_out_dir/courgette64.exe",