Clear opener when frame is detached.

third_party/WebKit/Source/web/tests/WebFrameTest.cpp

 /*
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 11383 matching lines @@
                                   &mainFrameClient);
 
   EXPECT_TRUE(mainFrameClient.childClient().didCallFrameDetached());
   EXPECT_TRUE(mainFrameClient.childClient().didCallDidStopLoading());
   EXPECT_TRUE(mainFrameClient.childClient().didCallDidFinishDocumentLoad());
   EXPECT_TRUE(mainFrameClient.childClient().didCallDidHandleOnloadEvents());
 
   webViewHelper.reset();
 }
 
+TEST_F(WebFrameTest, ClearClosedOpener) {
+  FrameTestHelpers::TestWebViewClient openerWebViewClient;
+  FrameTestHelpers::WebViewHelper openerHelper;
+  openerHelper.initialize(false, nullptr, &openerWebViewClient);
+  FrameTestHelpers::WebViewHelper helper;
+  helper.initializeWithOpener(openerHelper.webView()->mainFrame());
+
+  openerHelper.reset();
+  EXPECT_EQ(nullptr, helper.webView()->mainFrameImpl()->opener());
+}
+
 }  // namespace blink