NOT FOR LANDING Experiment with allocating SVGImageForContainer on demand

Source/core/layout/svg/LayoutSVGImage.cpp

 /*
  * Copyright (C) 2006 Alexander Kellett <lypanov@kde.org>
  * Copyright (C) 2006 Apple Computer, Inc.
  * Copyright (C) 2007 Nikolas Zimmermann <zimmermann@kde.org>
  * Copyright (C) 2007, 2008, 2009 Rob Buis <buis@kde.org>
  * Copyright (C) 2009 Google, Inc.
  * Copyright (C) 2009 Dirk Schulze <krit@webkit.org>
  * Copyright (C) 2010 Patrick Gansterer <paroga@paroga.com>
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 61 matching lines @@
     // scaling. This can be achieved by setting the image's container size to
     // its viewport size (i.e. if a viewBox is available - use that - else use intrinsic size.)
     // See: http://www.w3.org/TR/SVG/single-page.html, 7.8 The 'preserveAspectRatio' attribute.
     Length intrinsicWidth;
     Length intrinsicHeight;
     FloatSize intrinsicRatio;
     cachedImage.computeIntrinsicDimensions(intrinsicWidth, intrinsicHeight, intrinsicRatio);
     return intrinsicRatio;
 }
 
-static bool containerSizeIsSetForLayoutObject(ImageResource& cachedImage, const LayoutObject* layoutObject)
-{
-    const Image* image = cachedImage.image();
-    // If a container size has been specified for this layoutObject, then
-    // imageForLayoutObject() will return the SVGImageForContainer while image()
-    // will return the underlying SVGImage.
-    return !image->isSVGImage() || image != cachedImage.imageForLayoutObject(layoutObject);
-}
-
-void LayoutSVGImage::updateImageContainerSize()
-{
-    ImageResource* cachedImage = m_imageResource->cachedImage();
-    if (!cachedImage || !cachedImage->usesImageContainerSize())
-        return;
-    FloatSize imageViewportSize = computeImageViewportSize(*cachedImage);
-    if (LayoutSize(imageViewportSize) != m_imageResource->imageSize(styleRef().effectiveZoom())
-        || !containerSizeIsSetForLayoutObject(*cachedImage, this)) {
-        m_imageResource->setContainerSizeForLayoutObject(roundedIntSize(imageViewportSize));
-    }
-}
-
 void LayoutSVGImage::updateBoundingBox()
 {
     FloatRect oldBoundaries = m_objectBoundingBox;
 
     SVGLengthContext lengthContext(element());
     m_objectBoundingBox = FloatRect(
         lengthContext.valueForLength(styleRef().svgStyle().x(), styleRef(), SVGLengthMode::Width),
         lengthContext.valueForLength(styleRef().svgStyle().y(), styleRef(), SVGLengthMode::Height),
         lengthContext.valueForLength(styleRef().width(), styleRef(), SVGLengthMode::Width),
         lengthContext.valueForLength(styleRef().height(), styleRef(), SVGLengthMode::Height));
     m_needsBoundariesUpdate |= oldBoundaries != m_objectBoundingBox;
 }
 
 void LayoutSVGImage::layout()
 {
     ASSERT(needsLayout());
     LayoutAnalyzer::Scope analyzer(*this);
 
     updateBoundingBox();
-    updateImageContainerSize();
 
     bool transformOrBoundariesUpdate = m_needsTransformUpdate || m_needsBoundariesUpdate;
     if (m_needsTransformUpdate) {
         m_localTransform = toSVGImageElement(element())->calculateAnimatedLocalTransform();
         m_needsTransformUpdate = false;
     }
 
     if (m_needsBoundariesUpdate) {
         m_bufferedForeground.clear();
 
@@ skipping 45 matching lines @@
     return false;
 }
 
 void LayoutSVGImage::imageChanged(WrappedImagePtr, const IntRect*)
 {
     // Notify parent resources that we've changed. This also invalidates
     // references from resources (filters) that may have a cached
     // representation of this image/layout object.
     LayoutSVGResourceContainer::markForLayoutAndParentResourceInvalidation(this, false);
 
-    // Update the SVGImageCache sizeAndScales entry in case image loading finished after layout.
-    // (https://bugs.webkit.org/show_bug.cgi?id=99489)
-    updateImageContainerSize();
-
     m_bufferedForeground.clear();
 
     setShouldDoFullPaintInvalidation();
 }
 
 void LayoutSVGImage::addOutlineRects(Vector<LayoutRect>& rects, const LayoutPoint&) const
 {
     // this is called from paint() after the localTransform has already been applied
     rects.append(LayoutRect(paintInvalidationRectInLocalCoordinates()));
 }
 
 } // namespace blink