NOT FOR LANDING Experiment with allocating SVGImageForContainer on demand

Source/core/fetch/ImageResource.h

 /*
     Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)
     Copyright (C) 2001 Dirk Mueller <mueller@kde.org>
     Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
     Copyright (C) 2004, 2005, 2006, 2007 Apple 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 23 matching lines @@
 namespace blink {
 
 class ImageResourceClient;
 class FetchRequest;
 class ResourceFetcher;
 class FloatSize;
 class Length;
 class MemoryCache;
 class LayoutObject;
 class SecurityOrigin;
-class SVGImageForContainer;
 
 class CORE_EXPORT ImageResource final : public Resource, public ImageObserver {
     friend class MemoryCache;
 
 public:
     typedef ImageResourceClient ClientType;
 
     static ResourcePtr<ImageResource> fetch(FetchRequest&, ResourceFetcher*);
 
     ImageResource(blink::Image*);
     // Exposed for testing
     ImageResource(const ResourceRequest&, blink::Image*);
     ~ImageResource() override;
 
     void load(ResourceFetcher*, const ResourceLoaderOptions&) override;
 
     blink::Image* image(); // Returns the nullImage() if the image is not available yet.
     blink::Image* imageForLayoutObject(const LayoutObject*); // Returns the nullImage() if the image is not available yet.
     bool hasImage() const { return m_image.get(); }
     // Side effect: ensures decoded image is in cache, therefore should only be called when about to draw the image.
     // FIXME: Decoding image on the main thread is expensive, so rather than forcing decode, consider returning false
     // when image is not decoded yet, as we do in case of deferred decoding.
     bool currentFrameKnownToBeOpaque(const LayoutObject*);
 
     static std::pair<blink::Image*, float> brokenImage(float deviceScaleFactor); // Returns an image and the image's resolution scale factor.
     bool willPaintBrokenImage() const;
 
     bool canRender(const LayoutObject& layoutObject, float multiplier) { return !errorOccurred() && !imageSizeForLayoutObject(&layoutObject, multiplier).isEmpty(); }
 
-    void setContainerSizeForLayoutObject(const ImageResourceClient*, const IntSize&, float);
     bool usesImageContainerSize() const;
     bool imageHasRelativeWidth() const;
     bool imageHasRelativeHeight() const;
     // The device pixel ratio we got from the server for this image, or 1.0.
     float devicePixelRatioHeaderValue() const { return m_devicePixelRatioHeaderValue; }
     bool hasDevicePixelRatioHeaderValue() const { return m_hasDevicePixelRatioHeaderValue; }
 
     enum SizeType {
         NormalSize, // Report the size of the image associated with a certain layoutObject
         IntrinsicSize, // Report the intrinsic size, i.e. ignore whatever has been set extrinsically.
@@ skipping 49 matching lines @@
     ImageResource(const ResourceRequest&);
 
     void clear();
 
     void setCustomAcceptHeader();
     void createImage();
     void updateImage(bool allDataReceived);
     void clearImage();
     // If not null, changeRect is the changed part of the image.
     void notifyObservers(const IntRect* changeRect = nullptr);
-    IntSize svgImageSizeForLayoutObject(const LayoutObject*) const;
-    blink::Image* svgImageForLayoutObject(const LayoutObject*);
     bool loadingMultipartContent() const;
 
     float m_devicePixelRatioHeaderValue;
 
-    typedef HashMap<const ImageResourceClient*, RefPtr<SVGImageForContainer>> ImageForContainerMap;
-    OwnPtr<ImageForContainerMap> m_imageForContainerMap;
-
     RefPtr<blink::Image> m_image;
     bool m_hasDevicePixelRatioHeaderValue;
 };
 
 DEFINE_RESOURCE_TYPE_CASTS(Image);
 
 }
 
 #endif