Fix GN generation for WinASAN build

BUILD.gn

Index: BUILD.gn
diff --git a/BUILD.gn b/BUILD.gn
index 8bf24cc9db7cd7eb26121c8bb2606070fb0ca382..90d164322b2d744b493d872eb22ea01a484d897f 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -109,9 +109,13 @@ if (is_win) {
       "//courgette:copy_courgette_binaries",
       "//remoting/webapp",
     ]
-    if (target_cpu == "x86") {
-      deps += [ "//courgette(//build/toolchain/win:x64)" ]
 
+    if (target_cpu == "x86") {
+      if (is_clang) {
+        deps += [ "//courgette(//build/toolchain/win:clang_x64)" ]
+      } else {
+        deps += [ "//courgette(//build/toolchain/win:x64)" ]
+      }
       if (is_chrome_branded) {
         deps += [ "//remoting/host:remoting_host_installation" ]
       }