[gin] Fire observer after added when recording is in progress.

gin/BUILD.gn

 # Copyright 2014 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.
 
 import("//testing/test.gni")
 import("//v8/gni/v8.gni")
 
 # This is depended upon from the browser DLL on Windows, where V8 is not used,
 # but features are enabled. This cannot depend on V8.
 source_set("gin_features") {
@@ skipping 186 matching lines @@
     "converter_unittest.cc",
     "interceptor_unittest.cc",
     "modules/module_registry_unittest.cc",
     "modules/timer_unittest.cc",
     "per_context_data_unittest.cc",
     "shell/gin_shell_unittest.cc",
     "shell_runner_unittest.cc",
     "test/run_all_unittests.cc",
     "test/run_js_tests.cc",
     "v8_isolate_memory_dump_provider_unittest.cc",
+    "v8_platform_unittest.cc",
     "wrappable_unittest.cc",
   ]
 
   deps = [
     ":gin_shell",
     ":gin_test",
     "//base/test:test_support",
     "//v8",
   ]
 
   configs += [ "//v8:external_startup_data" ]
 
   data = [
     "modules/module_registry_unittests.js",
     "shell/hello_world.js",
     "test/file_unittests.js",
     "test/gtest_unittests.js",
     "../OWNERS",
   ]
 
   data_deps = [
     ":gin_shell",
   ]
 }