DevTools: implement release note behind an experiment

third_party/WebKit/Source/devtools/BUILD.gn

Index: third_party/WebKit/Source/devtools/BUILD.gn
diff --git a/third_party/WebKit/Source/devtools/BUILD.gn b/third_party/WebKit/Source/devtools/BUILD.gn
index 9957410584379297c24a1813d7c6d259bb8247c9..02100e2a94dea54d2d79a4ef7916aee35e37310d 100644
--- a/third_party/WebKit/Source/devtools/BUILD.gn
+++ b/third_party/WebKit/Source/devtools/BUILD.gn
@@ -141,6 +141,7 @@ all_devtools_files = [
   "front_end/console/ConsoleViewMessage.js",
   "front_end/console/ConsoleViewport.js",
   "front_end/console/module.json",
+  "front_end/console/releaseNoteMessage.css",
   "front_end/cookie_table/CookiesTable.js",
   "front_end/cookie_table/module.json",
   "front_end/css_tracker/cssTrackerView.css",
@@ -246,6 +247,8 @@ all_devtools_files = [
   "front_end/heap_snapshot_worker/HeapSnapshotWorker.js",
   "front_end/heap_snapshot_worker/HeapSnapshotWorkerDispatcher.js",
   "front_end/heap_snapshot_worker/module.json",
+  "front_end/help/module.json",
+  "front_end/help/ReleaseNoteManager.js",
   "front_end/host/InspectorFrontendHost.js",
   "front_end/host/InspectorFrontendHostAPI.js",
   "front_end/host/module.json",
@@ -820,6 +823,7 @@ generated_resources = [
   "$resources_out_dir/elements/elements_module.js",
   "$resources_out_dir/event_listeners/event_listeners_module.js",
   "$resources_out_dir/heap_snapshot_model/heap_snapshot_model_module.js",
+  "$resources_out_dir/help/help_module.js",
   "$resources_out_dir/inline_editor/inline_editor_module.js",
   "$resources_out_dir/layer_viewer/layer_viewer_module.js",
   "$resources_out_dir/layers/layers_module.js",