fix: crash on close window when webContents destroyed (#31620)

shell/browser/api/electron_api_browser_window.cc

@@ -254,7 +254,7 @@ void BrowserWindow::OnCloseButtonClicked(bool* prevent_default) {
     ScheduleUnresponsiveEvent(5000);
 
   // Already closed by renderer.
-  if (!web_contents())
+  if (!web_contents() || !api_web_contents_)
     return;
 
   // Required to make beforeunload handler work.

spec-main/api-browser-window-spec.ts

@@ -110,6 +110,11 @@ describe('BrowserWindow module', () => {
       await closed;
     });
 
+    it('should not crash if called after webContents is destroyed', () => {
+      w.webContents.destroy();
+      w.webContents.on('destroyed', () => w.close());
+    });
+
     it('should emit unload handler', async () => {
       await w.loadFile(path.join(fixtures, 'api', 'unload.html'));
       const closed = emittedOnce(w, 'closed');