Oilpan: have PageSerializer accurately handle its GCed references.

Source/core/page/PageSerializer.cpp

 /*
  * Copyright (C) 2011 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 60 matching lines @@
 namespace blink {
 
 static bool isCharsetSpecifyingNode(const Node& node)
 {
     if (!isHTMLMetaElement(node))
         return false;
 
     const HTMLMetaElement& element = toHTMLMetaElement(node);
     HTMLAttributeList attributeList;
     AttributeCollection attributes = element.attributes();
-    for (const Attribute& attr : attributes) {
+    for (const Attribute& attr: attributes) {
         // FIXME: We should deal appropriately with the attribute if they have a namespace.
         attributeList.append(std::make_pair(attr.name().localName(), attr.value().string()));
     }
     WTF::TextEncoding textEncoding = encodingFromMetaAttributes(attributeList);
     return textEncoding.isValid();
 }
 
 static bool shouldIgnoreElement(const Element& element)
 {
     return isHTMLScriptElement(element) || isHTMLNoScriptElement(element) || isCharsetSpecifyingNode(element);
 }
 
 static const QualifiedName& frameOwnerURLAttributeName(const HTMLFrameOwnerElement& frameOwner)
 {
     // FIXME: We should support all frame owners including applets.
     return isHTMLObjectElement(frameOwner) ? HTMLNames::dataAttr : HTMLNames::srcAttr;
 }
 
 class SerializerMarkupAccumulator final : public MarkupAccumulator {
+    STACK_ALLOCATED();
 public:
     SerializerMarkupAccumulator(PageSerializer*, const Document&, WillBeHeapVector<RawPtrWillBeMember<Node>>*);
     virtual ~SerializerMarkupAccumulator();
 
 protected:
     virtual void appendText(StringBuilder& out, Text&) override;
     virtual void appendElement(StringBuilder& out, Element&, Namespaces*) override;
     virtual void appendCustomAttributes(StringBuilder& out, const Element&, Namespaces*) override;
     virtual void appendEndTag(const Element&) override;
 
 private:
-    PageSerializer* m_serializer;
-    const Document& m_document;
+    RawPtrWillBeMember<PageSerializer> m_serializer;
+    RawPtrWillBeMember<const Document> m_document;
 };
 
 SerializerMarkupAccumulator::SerializerMarkupAccumulator(PageSerializer* serializer, const Document& document, WillBeHeapVector<RawPtrWillBeMember<Node>>* nodes)
     : MarkupAccumulator(nodes, ResolveAllURLs, nullptr)
     , m_serializer(serializer)
-    , m_document(document)
+    , m_document(&document)
 {
 }
 
 SerializerMarkupAccumulator::~SerializerMarkupAccumulator()
 {
 }
 
 void SerializerMarkupAccumulator::appendText(StringBuilder& out, Text& text)
 {
     Element* parent = text.parentElement();
     if (parent && !shouldIgnoreElement(*parent))
         MarkupAccumulator::appendText(out, text);
 }
 
 void SerializerMarkupAccumulator::appendElement(StringBuilder& out, Element& element, Namespaces* namespaces)
 {
     if (!shouldIgnoreElement(element))
         MarkupAccumulator::appendElement(out, element, namespaces);
 
     if (isHTMLHeadElement(element)) {
         out.appendLiteral("<meta charset=\"");
-        out.append(m_document.charset());
+        out.append(m_document->charset());
         out.appendLiteral("\">");
     }
 
     // FIXME: For object (plugins) tags and video tag we could replace them by an image of their current contents.
 }
 
 void SerializerMarkupAccumulator::appendCustomAttributes(StringBuilder& out, const Element& element, Namespaces* namespaces)
 {
     if (!element.isFrameOwnerElement())
         return;
@@ skipping 54 matching lines @@
         return;
     }
 
     WillBeHeapVector<RawPtrWillBeMember<Node>> serializedNodes;
     SerializerMarkupAccumulator accumulator(this, document, &serializedNodes);
     String text = accumulator.serializeNodes(document, IncludeNode);
     CString frameHTML = textEncoding.normalizeAndEncode(text, WTF::EntitiesForUnencodables);
     m_resources->append(SerializedResource(url, document.suggestedMIMEType(), SharedBuffer::create(frameHTML.data(), frameHTML.length())));
     m_resourceURLs.add(url);
 
-    for (Node* node : serializedNodes) {
+    for (Node* node: serializedNodes) {
         ASSERT(node);
         if (!node->isElementNode())
             continue;
 
         Element& element = toElement(*node);
         // We have to process in-line style as it might contain some resources (typically background images).
         if (element.isStyledElement())
             retrieveResourcesForProperties(element.inlineStyle(), document);
 
         if (isHTMLImageElement(element)) {
@@ skipping 94 matching lines @@
 
     RefPtr<SharedBuffer> data = imageRenderer ? image->imageForRenderer(imageRenderer)->data() : nullptr;
     if (!data)
         data = image->image()->data();
 
     addToResources(image, data, url);
 }
 
 void PageSerializer::addFontToResources(FontResource* font)
 {
-    if (!font || !shouldAddURL(font->url()) || !font->isLoaded() || !font->resourceBuffer()) {
+    if (!font || !shouldAddURL(font->url()) || !font->isLoaded() || !font->resourceBuffer())
         return;
-    }
+
     RefPtr<SharedBuffer> data(font->resourceBuffer());
 
     addToResources(font, data, font->url());
 }
 
 void PageSerializer::retrieveResourcesForProperties(const StylePropertySet* styleDeclaration, Document& document)
 {
     if (!styleDeclaration)
         return;
 
@@ skipping 26 matching lines @@
         addFontToResources(fontFaceSrcValue->fetch(&document));
     } else if (cssValue->isValueList()) {
         CSSValueList* cssValueList = toCSSValueList(cssValue);
         for (unsigned i = 0; i < cssValueList->length(); i++)
             retrieveResourcesForCSSValue(cssValueList->item(i), document);
     }
 }
 
 KURL PageSerializer::urlForBlankFrame(LocalFrame* frame)
 {
-    HashMap<LocalFrame*, KURL>::iterator iter = m_blankFrameURLs.find(frame);
+    BlankFrameURLMap::iterator iter = m_blankFrameURLs.find(frame);
     if (iter != m_blankFrameURLs.end())
         return iter->value;
     String url = "wyciwyg://frame/" + String::number(m_blankFrameCounter++);
     KURL fakeURL(ParsedURLString, url);
     m_blankFrameURLs.add(frame, fakeURL);
 
     return fakeURL;
 }
 
-}
+} // namespace blink