Handle focusability for plugin elements which has browsing context

third_party/WebKit/Source/core/html/HTMLPlugInElement.cpp

 /**
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Stefan Schimanski (1Stein@gmx.de)
  * Copyright (C) 2004, 2005, 2006 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 357 matching lines @@
 {
     // Needs to load the plugin immediatedly because this function is called
     // when JavaScript code accesses the plugin.
     // FIXME: Check if dispatching events here is safe.
     document().updateStyleAndLayoutIgnorePendingStylesheets(Document::RunPostLayoutTasksSynchronously);
     return existingLayoutPart();
 }
 
 bool HTMLPlugInElement::isKeyboardFocusable() const
 {
-    if (!document().isActive())
-        return false;
-    return pluginWidget() && pluginWidget()->isPluginView() && toPluginView(pluginWidget())->supportsKeyboardFocus();
+    if (HTMLFrameOwnerElement::isKeyboardFocusable())
+        return true;
+    return document().isActive() && pluginWidget() && pluginWidget()->isPluginView() && toPluginView(pluginWidget())->supportsKeyboardFocus();
 }
 
 bool HTMLPlugInElement::hasCustomFocusLogic() const
 {
     return !useFallbackContent();
 }
 
 bool HTMLPlugInElement::isPluginElement() const
 {
     return true;
@@ skipping 212 matching lines @@
 
 void HTMLPlugInElement::lazyReattachIfNeeded()
 {
     if (!useFallbackContent() && needsWidgetUpdate() && layoutObject() && !isImageType()) {
         lazyReattachIfAttached();
         setPersistedPluginWidget(nullptr);
     }
 }
 
 } // namespace blink