Validate origins when generating subdomain tokens

tools/origin_trials/validate_subdomain_origin/BUILD.gn

Index: tools/origin_trials/validate_subdomain_origin/BUILD.gn
diff --git a/tools/origin_trials/validate_subdomain_origin/BUILD.gn b/tools/origin_trials/validate_subdomain_origin/BUILD.gn
new file mode 100644
index 0000000000000000000000000000000000000000..d28b3ae1e022977a75a79d2c09d6fc38ae2048d8
--- /dev/null
+++ b/tools/origin_trials/validate_subdomain_origin/BUILD.gn
@@ -0,0 +1,20 @@
+# Copyright 2016 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+if (current_toolchain == host_toolchain) {
+  executable("validate_subdomain_origin") {
+    output_name = "validate_subdomain_origin"
+    sources = [
+      "validate_subdomain_origin.cc",
+    ]
+
+    configs += [ "//build/config/compiler:wexit_time_destructors" ]
+
+    deps = [
+      "//base",
+      "//net",
+      "//url",
+    ]
+  }
+}