Introduce lock screen app context to extension features

extensions/renderer/script_context.cc

Index: extensions/renderer/script_context.cc
diff --git a/extensions/renderer/script_context.cc b/extensions/renderer/script_context.cc
index e171e0fffae9fcd6ce23a0c856ba7f8897ec2039..46733a19cf8223ef10fca89c61c3919459b0d188 100644
--- a/extensions/renderer/script_context.cc
+++ b/extensions/renderer/script_context.cc
@@ -58,6 +58,8 @@ std::string GetContextTypeDescriptionString(Feature::Context context_type) {
       return "WEBUI";
     case Feature::SERVICE_WORKER_CONTEXT:
       return "SERVICE_WORKER";
+    case Feature::LOCK_SCREEN_EXTENSION_CONTEXT:
+      return "LOCK_SCREEN_EXTENSION";
   }
   NOTREACHED();
   return std::string();