Fix extension->id() nullptr access at TabCaptureAccessHandler::HandleRequest

chrome/browser/media/webrtc/tab_capture_access_handler.cc

Index: chrome/browser/media/webrtc/tab_capture_access_handler.cc
diff --git a/chrome/browser/media/webrtc/tab_capture_access_handler.cc b/chrome/browser/media/webrtc/tab_capture_access_handler.cc
index 7d18ea8bec74ae70703775e727c7d299389842b5..48f4c3471b4474a77b90ee517c13d06fe00a237b 100644
--- a/chrome/browser/media/webrtc/tab_capture_access_handler.cc
+++ b/chrome/browser/media/webrtc/tab_capture_access_handler.cc
@@ -42,9 +42,11 @@ void TabCaptureAccessHandler::HandleRequest(
   content::MediaStreamDevices devices;
   std::unique_ptr<content::MediaStreamUI> ui;
 
-  if (!extension)
+  if (!extension) {
     callback.Run(devices, content::MEDIA_DEVICE_TAB_CAPTURE_FAILURE,
                  std::move(ui));
+    return;
+  }
 
   Profile* profile =
       Profile::FromBrowserContext(web_contents->GetBrowserContext());