Revert of Move the Syzygy scripts out of //chrome/

third_party/kasko/BUILD.gn

Index: third_party/kasko/BUILD.gn
diff --git a/third_party/kasko/BUILD.gn b/third_party/kasko/BUILD.gn
index 49a837d10a21c55a485cf8545a592efdc6f78833..3db51a1b255bd0674f6f6d7417fb6af2d187c910 100644
--- a/third_party/kasko/BUILD.gn
+++ b/third_party/kasko/BUILD.gn
@@ -15,11 +15,8 @@
 if (enable_kasko) {
   assert(is_win, "Kasko only support Windows.")
   assert(target_cpu == "x86", "Kasko only support 32 bits.")
-
-  # TODO(sebmarchand): Fix this once the Kasko dependency in SyzyAsan has been
-  #     removed for the non-official builds.
-  #assert(is_chrome_branded,
-  #       "The Kasko client is only initialized in Chrome-branded builds.")
+  assert(is_chrome_branded,
+         "The Kasko client is only initialized in Chrome-branded builds.")
 
   config("kasko_config") {
     visibility = [ ":*" ]