Add webusb notification UI code

chrome/app/generated_resources.grd

Index: chrome/app/generated_resources.grd
diff --git a/chrome/app/generated_resources.grd b/chrome/app/generated_resources.grd
index 78e87b132c324a3981cb4f59b4f21ea97eda5f48..b8104b2a3a4b576bba63864301ed2548767db791 100644
--- a/chrome/app/generated_resources.grd
+++ b/chrome/app/generated_resources.grd
@@ -5384,6 +5384,14 @@ Keep your key file in a safe place. You will need it to create new versions of y
         Keep changes
       </message>
 
+      <!-- WebUsb Notification Flag -->
+      <message name="IDS_FLAGS_ENABLE_WEBUSB_NOTIFICATION_NAME" desc="Title for the flag which enables WebUsb notification.">
+        WebUsb notification.
+      </message>
+      <message name="IDS_FLAGS_ENABLE_WEBUSB_NOTIFICATION_DESCRIPTION" desc="Description for the flag which enables WebUsb notification.">
+        Experimental WebUsb notification.
+      </message>
+
       <!-- chrome://settings-frame/options_settings_app.html for the App Launcher Settings App -->
       <if expr="enable_settings_app">
         <message name="IDS_SETTINGS_APP_LAUNCHER_PRODUCT_NAME" desc="Product name to use when referring to applications running in the App Launcher inside the non-browser Settings App">