Ensure that every Document has a single, distinct template content ownerDocument

Source/core/dom/Document.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 503 matching lines @@
 
 Document::~Document()
 {
     ASSERT(!renderView());
     ASSERT(m_ranges.isEmpty());
     ASSERT(!parentTreeScope());
     ASSERT(!hasGuardRefCount());
     ASSERT(m_visibilityObservers.isEmpty());
 
     if (m_templateDocument)
-        m_templateDocument->setTemplateDocumentHost(0); // balanced in templateDocument().
+        m_templateDocument->m_templateDocumentHost = 0; // balanced in ensureTemplateDocument().
 
     m_scriptRunner.clear();
 
     removeAllEventListeners();
 
     // Currently we believe that Document can never outlive the parser.
     // Although the Document may be replaced synchronously, DocumentParsers
     // generally keep at least one reference to an Element which would in turn
     // has a reference to the Document.  If you hit this ASSERT, then that
     // assumption is wrong.  DocumentParser::detach() should ensure that even
@@ skipping 4780 matching lines @@
     if (locale.isEmpty() || !RuntimeEnabledFeatures::langAttributeAwareFormControlUIEnabled())
         return Locale::defaultLocale();
     LocaleIdentifierToLocaleMap::AddResult result = m_localeCache.add(localeKey, nullptr);
     if (result.isNewEntry)
         result.iterator->value = Locale::create(localeKey);
     return *(result.iterator->value);
 }
 
 Document& Document::ensureTemplateDocument()
 {
-    if (const Document* document = templateDocument())
-        return *const_cast<Document*>(document);
+    if (isTemplateDocument())
+        return *this;
+
+    if (m_templateDocument)
+        return *m_templateDocument;
 
     if (isHTMLDocument()) {
         DocumentInit init = DocumentInit::fromContext(contextDocument(), blankURL()).withNewRegistrationContext();
         m_templateDocument = HTMLDocument::create(init);
     } else {
         m_templateDocument = Document::create(DocumentInit(blankURL()));
     }
 
-    m_templateDocument->setTemplateDocumentHost(this); // balanced in dtor.
+    m_templateDocument->m_templateDocumentHost = this; // balanced in dtor.
 
     return *m_templateDocument.get();
 }
 
 void Document::didAssociateFormControl(Element* element)
 {
     if (!frame() || !frame()->page())
         return;
     m_associatedFormControls.add(element);
     if (!m_didAssociateFormControlsTimer.isActive())
@@ skipping 102 matching lines @@
 void Document::defaultEventHandler(Event* event)
 {
     if (frame() && frame()->remotePlatformLayer()) {
         frame()->chromeClient().forwardInputEvent(this, event);
         return;
     }
     Node::defaultEventHandler(event);
 }
 
 } // namespace WebCore