Make sure a container size is always set for SVG images in <svg:image>

Source/core/rendering/svg/RenderSVGImage.cpp

Index: Source/core/rendering/svg/RenderSVGImage.cpp
diff --git a/Source/core/rendering/svg/RenderSVGImage.cpp b/Source/core/rendering/svg/RenderSVGImage.cpp
index 5e4fa8188291b8064133a2eac15769ddc5ea7bf3..11200b437224fc8270c1fbbd0e22b30968f80011 100644
--- a/Source/core/rendering/svg/RenderSVGImage.cpp
+++ b/Source/core/rendering/svg/RenderSVGImage.cpp
@@ -77,6 +77,15 @@ FloatSize RenderSVGImage::computeImageViewportSize(ImageResource& cachedImage) c
     return intrinsicRatio;
 }
 
+static bool containerSizeIsSetForRenderer(ImageResource& cachedImage, const RenderObject* renderer)

[pdr., 2015/01/29 19:32:21]

Can we put this on ImageResource?

[fs, 2015/01/30 09:30:20]

I considered that, but since it didn't seem universally useful (to me) - since
this is a strange semantic that arises from the way m_svgImageCache is set
up/works. I.e. it'd look something like:

bool ImageResource::hasContainerSizeForRenderer(const ImageResourceClient*
renderer)
{
    ASSERT(renderer);
    if (!m_image)
        return m_pendingContainerSizeRequests.contains(renderer);
    if (!m_image->isSVGImage())
        return !m_image->usesContainerSize() || !m_image->size().isZero();
    return !!m_svgImageCache->imageForRenderer(renderer);
}

and some of that felt pretty hand-wavy... I can do it in a follow-up though if
you prefer.

+{
+    const Image* image = cachedImage.image();
+    // If a container size has been specified for this renderer, then
+    // imageForRenderer() will return the SVGImageForContainer while image()
+    // will return the underlying SVGImage.
+    return !image->isSVGImage() || image != cachedImage.imageForRenderer(renderer);
+}
+
 bool RenderSVGImage::updateImageViewport()
 {
     SVGImageElement* image = toSVGImageElement(element());
@@ -90,7 +99,8 @@ bool RenderSVGImage::updateImageViewport()
     ImageResource* cachedImage = m_imageResource->cachedImage();
     if (cachedImage && cachedImage->usesImageContainerSize()) {
         FloatSize imageViewportSize = computeImageViewportSize(*cachedImage);
-        if (LayoutSize(imageViewportSize) != m_imageResource->imageSize(style()->effectiveZoom())) {
+        if (LayoutSize(imageViewportSize) != m_imageResource->imageSize(style()->effectiveZoom())
+            || !containerSizeIsSetForRenderer(*cachedImage, this)) {
             m_imageResource->setContainerSizeForRenderer(roundedIntSize(imageViewportSize));
             updatedViewport = true;
         }