Have Node::document() return a reference instead of a pointer

Source/core/dom/ScriptLoader.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  * Copyright (C) 2008 Nikolas Zimmermann <zimmermann@kde.org>
  *
  * 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
@@ skipping 50 matching lines @@
     , m_isExternalScript(false)
     , m_alreadyStarted(alreadyStarted)
     , m_haveFiredLoad(false)
     , m_willBeParserExecuted(false)
     , m_readyToBeParserExecuted(false)
     , m_willExecuteWhenDocumentFinishedParsing(false)
     , m_forceAsync(!parserInserted)
     , m_willExecuteInOrder(false)
 {
     ASSERT(m_element);
-    if (parserInserted && element->document()->scriptableDocumentParser() && !element->document()->isInDocumentWrite())
-        m_startLineNumber = element->document()->scriptableDocumentParser()->lineNumber();
+    if (parserInserted && element->document().scriptableDocumentParser() && !element->document().isInDocumentWrite())
+        m_startLineNumber = element->document().scriptableDocumentParser()->lineNumber();
 }
 
 ScriptLoader::~ScriptLoader()
 {
     stopLoadRequest();
 }
 
 void ScriptLoader::insertedInto(ContainerNode* insertionPoint)
 {
     if (insertionPoint->inDocument() && !m_parserInserted)
@@ skipping 78 matching lines @@
             return true;
     } else if (MIMETypeRegistry::isSupportedJavaScriptMIMEType(type.stripWhiteSpace().lower()) || (supportLegacyTypes == AllowLegacyTypeInTypeAttribute && isLegacySupportedJavaScriptLanguage(type))) {
         return true;
     }
 
     return false;
 }
 
 Document* ScriptLoader::executingDocument() const
 {
-    Document* document = m_element->document();
-    if (!document->import())
-        return document;
-    return document->import()->master();
+    Document& document = m_element->document();
+    if (!document.import())
+        return &document;
+    return document.import()->master();
 }
 
 // http://dev.w3.org/html5/spec/Overview.html#prepare-a-script
 bool ScriptLoader::prepareScript(const TextPosition& scriptStartPosition, LegacyTypeSupport supportLegacyTypes)
 {
     if (m_alreadyStarted)
         return false;
 
     ScriptLoaderClient* client = this->client();
 
@@ skipping 20 matching lines @@
 
     if (wasParserInserted) {
         m_parserInserted = true;
         m_forceAsync = false;
     }
 
     m_alreadyStarted = true;
 
     // FIXME: If script is parser inserted, verify it's still in the original document.
     Document* executingDocument = this->executingDocument();
-    Document* elementDocument = m_element->document();
+    Document& elementDocument = m_element->document();
 
     // FIXME: Eventually we'd like to evaluate scripts which are inserted into a
     // viewless document but this'll do for now.
     // See http://bugs.webkit.org/show_bug.cgi?id=5727
     if (!executingDocument->frame())
         return false;
 
     if (!executingDocument->frame()->script()->canExecuteScripts(AboutToExecuteScript))
         return false;
 
     if (!isScriptForEventSupported())
         return false;
 
     if (!client->charsetAttributeValue().isEmpty())
         m_characterEncoding = client->charsetAttributeValue();
     else
-        m_characterEncoding = elementDocument->charset();
+        m_characterEncoding = elementDocument.charset();
 
     if (client->hasSourceAttribute()) {
         if (!fetchScript(client->sourceAttributeValue()))
             return false;
     }
 
     if (client->hasSourceAttribute() && client->deferAttributeValue() && m_parserInserted && !client->asyncAttributeValue()) {
         m_willExecuteWhenDocumentFinishedParsing = true;
         m_willBeParserExecuted = true;
     } else if (client->hasSourceAttribute() && m_parserInserted && !client->asyncAttributeValue()) {
         m_willBeParserExecuted = true;
-    } else if (!client->hasSourceAttribute() && m_parserInserted && !elementDocument->haveStylesheetsAndImportsLoaded()) {
+    } else if (!client->hasSourceAttribute() && m_parserInserted && !elementDocument.haveStylesheetsAndImportsLoaded()) {
         m_willBeParserExecuted = true;
         m_readyToBeParserExecuted = true;
     } else if (client->hasSourceAttribute() && !client->asyncAttributeValue() && !m_forceAsync) {
         m_willExecuteInOrder = true;
         executingDocument->scriptRunner()->queueScriptForExecution(this, m_resource, ScriptRunner::IN_ORDER_EXECUTION);
         m_resource->addClient(this);
     } else if (client->hasSourceAttribute()) {
         executingDocument->scriptRunner()->queueScriptForExecution(this, m_resource, ScriptRunner::ASYNC_EXECUTION);
         m_resource->addClient(this);
     } else {
         // Reset line numbering for nested writes.
-        TextPosition position = elementDocument->isInDocumentWrite() ? TextPosition() : scriptStartPosition;
-        KURL scriptURL = (!elementDocument->isInDocumentWrite() && m_parserInserted) ? elementDocument->url() : KURL();
+        TextPosition position = elementDocument.isInDocumentWrite() ? TextPosition() : scriptStartPosition;
+        KURL scriptURL = (!elementDocument.isInDocumentWrite() && m_parserInserted) ? elementDocument.url() : KURL();
         executeScript(ScriptSourceCode(scriptContent(), scriptURL, position));
     }
 
     return true;
 }
 
 bool ScriptLoader::fetchScript(const String& sourceUrl)
 {
     ASSERT(m_element);
 
-    RefPtr<Document> elementDocument = m_element->document();
+    RefPtr<Document> elementDocument = &m_element->document();
     if (!m_element->dispatchBeforeLoadEvent(sourceUrl))
         return false;
-    if (!m_element->inDocument() || m_element->document() != elementDocument)
+    if (!m_element->inDocument() || &m_element->document() != elementDocument)
         return false;
 
     ASSERT(!m_resource);
     if (!stripLeadingAndTrailingHTMLSpaces(sourceUrl).isEmpty()) {
         FetchRequest request(ResourceRequest(elementDocument->completeURL(sourceUrl)), m_element->localName());
 
         String crossOriginMode = m_element->fastGetAttribute(HTMLNames::crossoriginAttr);
         if (!crossOriginMode.isNull()) {
             StoredCredentials allowCredentials = equalIgnoringCase(crossOriginMode, "use-credentials") ? AllowStoredCredentials : DoNotAllowStoredCredentials;
             request.setPotentiallyCrossOriginEnabled(elementDocument->securityOrigin(), allowCredentials);
@@ skipping 27 matching lines @@
 }
 
 void ScriptLoader::executeScript(const ScriptSourceCode& sourceCode)
 {
     ASSERT(m_alreadyStarted);
 
     if (sourceCode.isEmpty())
         return;
 
     RefPtr<Document> executingDocument = this->executingDocument();
-    RefPtr<Document> elementDocument = m_element->document();
+    RefPtr<Document> elementDocument = &m_element->document();
     Frame* frame = executingDocument->frame();
 
     bool shouldBypassMainWorldContentSecurityPolicy = (frame && frame->script()->shouldBypassMainWorldContentSecurityPolicy()) || elementDocument->contentSecurityPolicy()->allowScriptNonce(m_element->fastGetAttribute(HTMLNames::nonceAttr));
 
     if (!m_isExternalScript && (!shouldBypassMainWorldContentSecurityPolicy && !elementDocument->contentSecurityPolicy()->allowInlineScript(elementDocument->url(), m_startLineNumber)))
         return;
 
     if (m_isExternalScript && m_resource && !m_resource->mimeTypeAllowedByNosniff()) {
         executingDocument->addConsoleMessage(SecurityMessageSource, ErrorMessageLevel, "Refused to execute script from '" + m_resource->url().elidedString() + "' because its MIME type ('" + m_resource->mimeType() + "') is not executable, and strict MIME type checking is enabled.");
         return;
     }
 
     if (frame) {
         IgnoreDestructiveWriteCountIncrementer ignoreDesctructiveWriteCountIncrementer(m_isExternalScript ? executingDocument.get() : 0);
 
         if (isHTMLScriptLoader(m_element))
             executingDocument->pushCurrentScript(toHTMLScriptElement(m_element));
 
         AccessControlStatus corsCheck = NotSharableCrossOrigin;
-        if (sourceCode.resource() && sourceCode.resource()->passesAccessControlCheck(m_element->document()->securityOrigin()))
+        if (sourceCode.resource() && sourceCode.resource()->passesAccessControlCheck(m_element->document().securityOrigin()))
             corsCheck = SharableCrossOrigin;
 
         // Create a script from the script element node, using the script
         // block's source and the script block's type.
         // Note: This is where the script is compiled and actually executed.
         frame->script()->executeScriptInMainWorld(sourceCode, corsCheck);
 
         if (isHTMLScriptLoader(m_element)) {
             ASSERT(executingDocument->currentScript() == m_element);
             executingDocument->popCurrentScript();
@@ skipping 21 matching lines @@
         dispatchLoadEvent();
     }
     resource->removeClient(this);
 }
 
 void ScriptLoader::notifyFinished(Resource* resource)
 {
     ASSERT(!m_willBeParserExecuted);
 
     RefPtr<Document> executingDocument = this->executingDocument();
-    RefPtr<Document> elementDocument = m_element->document();
+    RefPtr<Document> elementDocument = &m_element->document();
 
     // Resource possibly invokes this notifyFinished() more than
     // once because ScriptLoader doesn't unsubscribe itself from
     // Resource here and does it in execute() instead.
     // We use m_resource to check if this function is already called.
     ASSERT_UNUSED(resource, resource == m_resource);
     if (!m_resource)
         return;
     if (!elementDocument->fetcher()->canAccess(m_resource.get())) {
         dispatchErrorEvent();
@@ skipping 51 matching lines @@
     if (isHTMLScriptLoader(element))
         return toHTMLScriptElement(element)->loader();
 
     if (isSVGScriptLoader(element))
         return toSVGScriptElement(element)->loader();
 
     return 0;
 }
 
 }