Prepare SVGImage for the default sizing algorithm

third_party/WebKit/Source/core/svg/graphics/SVGImage.h

 /*
  * Copyright (C) 2006 Eric Seidel <eric@webkit.org>
  * Copyright (C) 2009 Apple 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:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 37 matching lines @@
     {
         return adoptRef(new SVGImage(observer));
     }
 
     static bool isInSVGImage(const Node*);
 
     LayoutBox* embeddedContentBox() const;
 
     bool isSVGImage() const override { return true; }
     bool isTextureBacked() override { return false; }
-    IntSize size() const override { return m_intrinsicSize; }
+    IntSize size() const override { return m_concreteObjectSize; }
 
     bool currentFrameHasSingleSecurityOrigin() const override;
 
     void startAnimation(CatchUpAnimation = CatchUp) override;
     void stopAnimation() override;
     void resetAnimation() override;
 
     // Advances an animated image. This will trigger an animation update for CSS
     // and advance the SMIL timeline by one frame.
     void advanceAnimationForTesting() override;
@@ skipping 14 matching lines @@
 
 private:
     friend class AXLayoutObject;
     friend class SVGImageChromeClient;
     friend class SVGImageForContainer;
 
     ~SVGImage() override;
 
     String filenameExtension() const override;
 
+    FloatSize calculateConcreteObjectSize(const FloatSize&) const;

[pdr., 2016/02/23 04:42:28]

Is this FloatSize parameter needed? Can you just return an IntSize here?

[davve, 2016/02/23 08:34:37]

I agree is looks a bit silly now, but it's used in the follow-up CL:

https://codereview.chromium.org/1694263003/

I return a FloatSize in order to decide on how to do rounding in as few places
as possible.

     IntSize containerSize() const;
     bool usesContainerSize() const override { return true; }
     void computeIntrinsicDimensions(Length& intrinsicWidth, Length& intrinsicHeight, FloatSize& intrinsicRatio) override;
 
     bool dataChanged(bool allDataReceived) override;
 
     // FIXME: SVGImages are underreporting decoded sizes and will be unable
     // to prune because these functions are not implemented yet.
     void destroyDecodedData(bool) override { }
 
     // FIXME: Implement this to be less conservative.
     bool currentFrameKnownToBeOpaque(MetadataMode = UseCurrentMetadata) override { return false; }
 
     SVGImage(ImageObserver*);
     void draw(SkCanvas*, const SkPaint&, const FloatRect& fromRect, const FloatRect& toRect, RespectImageOrientationEnum, ImageClampingMode) override;
     void drawForContainer(SkCanvas*, const SkPaint&, const FloatSize, float, const FloatRect&, const FloatRect&, const KURL&);
     void drawPatternForContainer(GraphicsContext&, const FloatSize, float, const FloatRect&, const FloatSize&, const FloatPoint&,
         SkXfermode::Mode, const FloatRect&, const FloatSize& repeatSpacing, const KURL&);
     PassRefPtr<SkImage> imageForCurrentFrameForContainer(const KURL&);
     void drawInternal(SkCanvas*, const SkPaint&, const FloatRect& fromRect, const FloatRect& toRect, RespectImageOrientationEnum,
         ImageClampingMode, const KURL&);
 
     OwnPtrWillBePersistent<SVGImageChromeClient> m_chromeClient;
     OwnPtrWillBePersistent<Page> m_page;
-    IntSize m_intrinsicSize;
+    IntSize m_concreteObjectSize;

[pdr., 2016/02/23 04:42:28]

Can you add a comment here describing what the concrete object size is?

It may be useful to add a markdown file describing sizing in SVG in general (as
a followup).

[davve, 2016/02/23 08:34:37]

I copy a snippet from the spec and provide a link.
Noted.

 };
 
 DEFINE_IMAGE_TYPE_CASTS(SVGImage);
 
 class ImageObserverDisabler {
     STACK_ALLOCATED();
     WTF_MAKE_NONCOPYABLE(ImageObserverDisabler);
 public:
     ImageObserverDisabler(Image* image)
         : m_image(image)
     {
         m_observer = m_image->imageObserver();
         m_image->setImageObserver(0);
     }
 
     ~ImageObserverDisabler()
     {
         m_image->setImageObserver(m_observer);
     }
 private:
     Image* m_image;
     RawPtrWillBeMember<ImageObserver> m_observer;
 };
 
 } // namespace blink
 
 #endif // SVGImage_h