src: use PauseOnNextJavascriptStatement to implement --inspect-brk-node

Instead of using the `debugger;` statement which is visible in the
JS source code and makes primordials.js environment-dependent.

PR-URL: #26034
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Gus Caplan <me@gus.host>
Reviewed-By: James M Snell <jasnell@gmail.com>

lib/internal/bootstrap/primordials.js

@@ -1,6 +1,6 @@
 'use strict';
 
-/* global breakAtBootstrap, primordials */
+/* global primordials */
 
 // This file subclasses and stores the JS builtins that come from the VM
 // so that Node.js's builtin modules do not need to later look these up from
@@ -12,10 +12,6 @@
 // `primordials.Object` where `primordials` is a lexical variable passed
 // by the native module compiler.
 
-if (breakAtBootstrap) {
-  debugger;  // eslint-disable-line no-debugger
-}
-
 function copyProps(src, dest) {
   for (const key of Reflect.ownKeys(src)) {
     if (!Reflect.getOwnPropertyDescriptor(dest, key)) {

src/node.cc

@@ -249,14 +249,18 @@ MaybeLocal<Value> RunBootstrapping(Environment* env) {
   // Store primordials
   env->set_primordials(Object::New(isolate));
   std::vector<Local<String>> primordials_params = {
-    FIXED_ONE_BYTE_STRING(isolate, "breakAtBootstrap"),
     env->primordials_string()
   };
   std::vector<Local<Value>> primordials_args = {
-    Boolean::New(isolate,
-                  env->options()->debug_options().break_node_first_line),
     env->primordials()
   };
+
+#if HAVE_INSPECTOR
+  if (env->options()->debug_options().break_node_first_line) {
+    env->inspector_agent()->PauseOnNextJavascriptStatement(
+        "Break at bootstrap");
+  }
+#endif  // HAVE_INSPECTOR
   MaybeLocal<Value> primordials_ret =
       ExecuteBootstrapper(env,
                           "internal/bootstrap/primordials",