fix: vibrant view is inserted into Views API hierarchy (#42263)

shell/browser/native_window_mac.h

@@ -12,6 +12,7 @@
 #include <string>
 #include <vector>
 
+#include "base/memory/raw_ptr.h"
 #include "electron/shell/common/api/api.mojom.h"
 #include "shell/browser/native_window.h"
 #include "ui/display/display_observer.h"
@@ -299,6 +300,9 @@ class NativeWindowMac : public NativeWindow,
 
   std::string vibrancy_type_;
 
+  // A views::NativeViewHost wrapping the vibrant view. Owned by the root view.
+  raw_ptr<views::NativeViewHost> vibrant_native_view_host_ = nullptr;
+
   // The presentation options before entering simple fullscreen mode.
   NSApplicationPresentationOptions simple_fullscreen_options_;
 };