Use srcset's resource pixel density to determine intrinsic size

Source/core/rendering/RenderImage.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2003, 2004, 2005, 2006, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2011-2012. All rights reserved.
  *
@@ skipping 41 matching lines @@
 
 namespace WebCore {
 
 using namespace HTMLNames;
 
 RenderImage::RenderImage(Element* element)
     : RenderReplaced(element, IntSize())
     , m_needsToSetSizeForAltText(false)
     , m_didIncrementVisuallyNonEmptyPixelCount(false)
     , m_isGeneratedContent(false)
+    , m_intrinsicSizeFactor(1.0f)
 {
     updateAltText();
 }
 
 RenderImage* RenderImage::createAnonymous(Document* document)
 {
     RenderImage* image = new RenderImage(0);
     image->setDocumentForAnonymous(document);
     return image;
 }
@@ skipping 531 matching lines @@
     if (!m_imageResource)
         return 0;
 
     ImageResource* cachedImage = m_imageResource->cachedImage();
     if (cachedImage && cachedImage->image() && cachedImage->image()->isSVGImage())
         return toSVGImage(cachedImage->image())->embeddedContentBox();
 
     return 0;
 }
 
+LayoutSize RenderImage::intrinsicSize() const OVERRIDE
+{

[pdr., 2013/10/11 05:17:33]

Can you add an assert here:
ASSERT(m_imageResource);

[Yoav Weiss, 2013/10/11 07:22:32]

Sure

+    LayoutSize intrinsic = RenderReplaced::intrinsicSize();
+    ImageResource* cachedImage = m_imageResource->cachedImage();
+    if (cachedImage && cachedImage->image() && cachedImage->image()->isSVGImage())

[pdr., 2013/10/11 05:17:33]

I don't understand the cachedImage->image()->isSVGImage() check here. Shouldn't
this apply to all images?

[Yoav Weiss, 2013/10/11 07:22:32]

It should. Applying it to bitmaps breaks them. Currently, I'm not sure why.
I'll see if I can come up with a good explanation as to why this works the way
it does.

+        intrinsic.scale(m_intrinsicSizeFactor);
+    return intrinsic;
+}
+
+LayoutSize RenderImage::unscaledIntrinsicSize() const
+{
+    return RenderReplaced::intrinsicSize();
+}
+
 } // namespace WebCore