Fix crash when an onorientationchange event detaches an iframe.

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 7700 matching lines @@
     EXPECT_CALL(client, didOverscroll(WebFloatSize(-10, 0), WebFloatSize(-20, -30), WebFloatPoint(33, 33), WebFloatSize()));
     ScrollUpdate(&webViewHelper, 30, 0);
     Mock::VerifyAndClearExpectations(&client);
 
     // Overscroll is not reported.
     EXPECT_CALL(client, didOverscroll(WebFloatSize(), WebFloatSize(), WebFloatPoint(33, 33), WebFloatSize())).Times(0);
     ScrollEnd(&webViewHelper);
     Mock::VerifyAndClearExpectations(&client);
 }
 
+TEST_F(WebFrameTest, OrientationFrameDetach)
+{
+    RuntimeEnabledFeatures::setOrientationEventEnabled(true);
+    registerMockedHttpURLLoad("orientation-frame-detach.html");
+    FrameTestHelpers::WebViewHelper webViewHelper;
+    WebViewImpl* webViewImpl = webViewHelper.initializeAndLoad(m_baseURL + "orientation-frame-detach.html", true);
+    webViewImpl->mainFrameImpl()->sendOrientationChangeEvent();
+}
+
 } // namespace blink