Add a scoping object to help block scripting during plugin destruction.

Source/core/frame/LocalFrame.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Simon Hausmann <hausmann@kde.org>
  *                     2000 Stefan Schimanski <1Stein@gmx.de>
  *                     2001 George Staikos <staikos@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2005 Alexey Proskuryakov <ap@nypop.com>
  * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)
@@ skipping 47 matching lines @@
 #include "core/layout/compositing/DeprecatedPaintLayerCompositor.h"
 #include "core/loader/FrameLoadRequest.h"
 #include "core/loader/FrameLoaderClient.h"
 #include "core/page/FocusController.h"
 #include "core/page/Page.h"
 #include "core/page/scrolling/ScrollingCoordinator.h"
 #include "core/paint/DeprecatedPaintLayer.h"
 #include "core/paint/TransformRecorder.h"
 #include "core/svg/SVGDocumentExtensions.h"
 #include "platform/DragImage.h"
+#include "platform/PluginScriptForbiddenScope.h"
 #include "platform/RuntimeEnabledFeatures.h"
 #include "platform/ScriptForbiddenScope.h"
 #include "platform/graphics/GraphicsContext.h"
 #include "platform/graphics/ImageBuffer.h"
 #include "platform/graphics/paint/ClipRecorder.h"
 #include "platform/graphics/paint/DisplayItemListContextRecorder.h"
 #include "platform/text/TextStream.h"
 #include "wtf/PassOwnPtr.h"
 #include "wtf/StdLibExtras.h"
 
@@ skipping 189 matching lines @@
             nullptr, m_loader.resourceRequestForReload(loadType, KURL(), clientRedirectPolicy));
         request.setClientRedirect(clientRedirectPolicy);
         m_loader.load(request, loadType);
     } else {
         m_navigationScheduler.scheduleReload();
     }
 }
 
 void LocalFrame::detach()
 {
+    PluginScriptForbiddenScope forbidPluginDestructorScripting;
     // A lot of the following steps can result in the current frame being
     // detached, so protect a reference to it.
     RefPtrWillBeRawPtr<LocalFrame> protect(this);
     m_loader.stopAllLoaders();
     m_loader.dispatchUnloadEvent();
     detachChildren();
     // stopAllLoaders() needs to be called after detachChildren(), because detachChildren()
     // will trigger the unload event handlers of any child frames, and those event
     // handlers might start a new subresource load in this frame.
     m_loader.stopAllLoaders();
@@ skipping 536 matching lines @@
     , m_textZoomFactor(parentTextZoomFactor(this))
     , m_inViewSourceMode(false)
 {
     if (isLocalRoot())
         m_instrumentingAgents = InstrumentingAgents::create();
     else
         m_instrumentingAgents = localFrameRoot()->m_instrumentingAgents;
 }
 
 } // namespace blink