Collapse images disallowed by the Safe Browsing Subresource Filter.

third_party/WebKit/Source/core/html/HTMLImageElement.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2004, 2008, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  *
  * 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 84 matching lines @@
   bool hasPendingActivity() const final {
     return imageLoader().hasPendingActivity();
   }
 
   bool canContainRangeEndPoint() const override { return false; }
 
   const AtomicString imageSourceURL() const override;
 
   HTMLFormElement* formOwner() const override;
   void formRemovedFromTree(const Node& formRoot);
-  virtual void ensureFallbackContent();
+  virtual void ensureCollapsedOrFallbackContent();
   virtual void ensureFallbackForGeneratedContent();
   virtual void ensurePrimaryContent();
 
   // CanvasImageSource implementation
   PassRefPtr<Image> getSourceImageForCanvas(SourceImageStatus*,
                                             AccelerationHint,
                                             SnapshotReason,
                                             const FloatSize&) const override;
   bool isSVGSource() const override;
   bool wouldTaintOrigin(SecurityOrigin*) const override;
   FloatSize elementSize(const FloatSize&) const override;
   FloatSize defaultDestinationSize(const FloatSize&) const override;
   const KURL& sourceURL() const override;
   bool isAccelerated() const override { return false; }
   bool isOpaque() const override;
   int sourceWidth() override;
   int sourceHeight() override;
 
   // public so that HTMLPictureElement can call this as well.
   void selectSourceURL(ImageLoader::UpdateFromElementBehavior);
-  void reattachFallbackContent();
+  void reattachContent();
   void setUseFallbackContent();
   void setIsFallbackImage() { m_isFallbackImage = true; }
 
   FetchRequest::ResourceWidth getResourceWidth();
   float sourceSize(Element&);
 
   void forceReload() const;
 
   // ImageBitmapSource implementation
   IntSize bitmapSourceSize() const override;
   ScriptPromise createImageBitmap(ScriptState*,
                                   EventTarget&,
                                   Optional<IntRect> cropRect,
                                   const ImageBitmapOptions&,
                                   ExceptionState&) override;
 
  protected:
+  enum class ContentType : uint8_t { Primary, Fallback, Collapsed };
+
   explicit HTMLImageElement(Document&,
                             HTMLFormElement* = 0,
                             bool createdByParser = false);
 
   void didMoveToNewDocument(Document& oldDocument) override;
-  virtual bool useFallbackContent() const { return m_useFallbackContent; }
+  virtual bool useFallbackContent() const {
+    return m_contentType == ContentType::Fallback;
+  }
 
   void didAddUserAgentShadowRoot(ShadowRoot&) override;
   PassRefPtr<ComputedStyle> customStyleForLayoutObject() override;
 
  private:
   bool areAuthorShadowsAllowed() const override { return false; }
 
   void parseAttribute(const QualifiedName&,
                       const AtomicString&,
                       const AtomicString&) override;
   bool isPresentationAttribute(const QualifiedName&) const override;
   void collectStyleForPresentationAttribute(const QualifiedName&,
                                             const AtomicString&,
                                             MutableStylePropertySet*) override;
 
   void attachLayoutTree(const AttachContext& = AttachContext()) override;
+  bool layoutObjectIsNeeded(const ComputedStyle&) override;
   LayoutObject* createLayoutObject(const ComputedStyle&) override;
 
   bool canStartSelection() const override { return false; }
 
   bool isURLAttribute(const Attribute&) const override;
   bool hasLegalLinkAttribute(const QualifiedName&) const override;
   const QualifiedName& subResourceAttributeName() const override;
 
   bool draggable() const override;
 
@@ skipping 10 matching lines @@
   HTMLImageLoader& imageLoader() const { return *m_imageLoader; }
   void notifyViewportChanged();
   void createMediaQueryListIfDoesNotExist();
 
   Member<HTMLImageLoader> m_imageLoader;
   Member<ViewportChangeListener> m_listener;
   Member<HTMLFormElement> m_form;
   AtomicString m_bestFitImageURL;
   float m_imageDevicePixelRatio;
   Member<HTMLSourceElement> m_source;
+  ContentType m_contentType;

[Mike West, 2016/11/30 15:57:35]

Nit: "LayoutDisposition", perhaps? `ContentType` means too many things already
(`Content-Type` HTTP header, for instance).

[engedy, 2016/11/30 17:37:39]

Good point. LayoutDisposition sounds good, done.

   unsigned m_formWasSetByParser : 1;
   unsigned m_elementCreatedByParser : 1;
-  unsigned m_useFallbackContent : 1;
   unsigned m_isFallbackImage : 1;
 
   ReferrerPolicy m_referrerPolicy;
 };
 
 }  // namespace blink
 
 #endif  // HTMLImageElement_h