fix: keep references to active menus created by api Menu (electron#19427

)

Without this such menus would be destroyed by js garbage collector even
when they are still displayed.

shell/browser/api/atom_api_menu.cc

@@ -4,6 +4,8 @@
 
 #include "shell/browser/api/atom_api_menu.h"
 
+#include <map>
+
 #include "native_mate/constructor.h"
 #include "native_mate/dictionary.h"
 #include "native_mate/object_template_builder.h"
@@ -14,6 +16,13 @@
 #include "shell/common/native_mate_converters/string16_converter.h"
 #include "shell/common/node_includes.h"
 
+namespace {
+// We need this map to keep references to currently opened menus.
+// Without this menus would be destroyed by js garbage collector
+// even when they are still displayed.
+std::map<uint32_t, v8::Global<v8::Object>> g_menus;
+}  // unnamed namespace
+
 namespace electron {
 
 namespace api {
@@ -200,10 +209,12 @@ bool Menu::WorksWhenHiddenAt(int index) const {
 }
 
 void Menu::OnMenuWillClose() {
+  g_menus.erase(weak_map_id());
   Emit("menu-will-close");
 }
 
 void Menu::OnMenuWillShow() {
+  g_menus[weak_map_id()] = v8::Global<v8::Object>(isolate(), GetWrapper());
   Emit("menu-will-show");
 }