src: destroy inspector agent before context

The inspector_agent depends on the context still being accessible
during the destructor execution.

PR-URL: nodejs/node#16472
Fixes: nodejs/node#15558
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Eugene Ostroukhov <eostroukhov@google.com>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Anna Henningsen <anna@addaleax.net>

src/env-inl.h

@@ -279,7 +279,7 @@ inline Environment::Environment(IsolateData* isolate_data,
       emit_napi_warning_(true),
       makecallback_cntr_(0),
 #if HAVE_INSPECTOR
-      inspector_agent_(this),
+      inspector_agent_(new inspector::Agent(this)),
 #endif
       http_parser_buffer_(nullptr),
       fs_stats_field_array_(nullptr),
@@ -319,6 +319,11 @@ inline Environment::Environment(IsolateData* isolate_data,
 inline Environment::~Environment() {
   v8::HandleScope handle_scope(isolate());
 
+#if HAVE_INSPECTOR
+  // Destroy inspector agent before erasing the context.
+  delete inspector_agent_;
+#endif
+
   context()->SetAlignedPointerInEmbedderData(kContextEmbedderDataIndex,
                                              nullptr);
 #define V(PropertyName, TypeName) PropertyName ## _.Reset();

src/env.h

@@ -712,8 +712,8 @@ class Environment {
 #undef V
 
 #if HAVE_INSPECTOR
-  inline inspector::Agent* inspector_agent() {
-    return &inspector_agent_;
+  inline inspector::Agent* inspector_agent() const {
+    return inspector_agent_;
   }
 #endif
 
@@ -767,7 +767,7 @@ class Environment {
   std::map<std::string, uint64_t> performance_marks_;
 
 #if HAVE_INSPECTOR
-  inspector::Agent inspector_agent_;
+  inspector::Agent* const inspector_agent_;
 #endif
 
   HandleWrapQueue handle_wrap_queue_;