Add WebAuthn Tab

This is the first commit for the WebAuthn DevTools front-end feature.

This patch:
- registers the feature as an experiment
- creates the top toolbar with a (non-functioning) toggle
- makes the feature accessible through the DevTools panel

Design Doc: https://docs.google.com/document/d/1A-cn0rxuHHAyGhywayk7xcTqSsR2X7va6H4kSMThOoY
Bug: 1034663

Change-Id: I91daca8e54b0dc6c0e2fd1e71b34e0e932fd8734
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/2231519
Reviewed-by: Tim van der Lippe <[email protected]>
Reviewed-by: Jan Scheffler <[email protected]>
Reviewed-by: Nina Satragno <[email protected]>
Commit-Queue: Tim van der Lippe <[email protected]>
Auto-Submit: Fawaz Mohammad <[email protected]>
diff --git a/BUILD.gn b/BUILD.gn
index 067e61f..b1d357b 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -367,6 +367,8 @@
   "front_end/web_audio/audioContextSelector.css",
   "front_end/web_audio/module.json",
   "front_end/web_audio/webAudio.css",
+  "front_end/webauthn/module.json",
+  "front_end/webauthn/webauthnPane.css",
   "front_end/worker_main/module.json",
   "front_end/worker_service/module.json",
   "front_end/workspace_diff/module.json",
@@ -570,6 +572,8 @@
   "wasmparser_worker/wasmparser_worker.js",
   "web_audio/web_audio.js",
   "web_audio/web_audio-legacy.js",
+  "webauthn/webauthn.js",
+  "webauthn/webauthn-legacy.js",
   "worker_main/worker_main.js",
   "worker_main/worker_main-legacy.js",
   "worker_service/worker_service.js",
@@ -839,6 +843,7 @@
   "$resources_out_dir/timeline_model/timeline_model_module.js",
   "$resources_out_dir/timeline/timeline_module.js",
   "$resources_out_dir/web_audio/web_audio_module.js",
+  "$resources_out_dir/webauthn/webauthn_module.js",
   "$resources_out_dir/workspace_diff/workspace_diff_module.js",
 ]
 
@@ -1607,6 +1612,7 @@
   "web_audio/graph_visualizer/NodeView.js",
   "web_audio/WebAudioModel.js",
   "web_audio/WebAudioView.js",
+  "webauthn/WebauthnPane.js",
   "worker_main/WorkerMain.js",
   "worker_service/ServiceDispatcher.js",
   "workspace_diff/WorkspaceDiff.js",