Should not crash when background image a display:none presents on the root

Source/core/layout/LayoutBox.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2005 Allan Sandfeld Jensen (kde@carewolf.com)
  *           (C) 2005, 2006 Samuel Weinig (sam.weinig@gmail.com)
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated. 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
@@ skipping 1127 matching lines @@
 
 void LayoutBox::paintBoxDecorationBackground(const PaintInfo& paintInfo, const LayoutPoint& paintOffset)
 {
     BoxPainter(*this).paintBoxDecorationBackground(paintInfo, paintOffset);
 }
 
 
 bool LayoutBox::getBackgroundPaintedExtent(LayoutRect& paintedExtent)
 {
     ASSERT(hasBackground());
+
+    // LayoutView is special in the sense that it expands to the whole canvas,
+    // thus can't be handled by this function.
+    ASSERT(!isLayoutView());
+
     LayoutRect backgroundRect(enclosingIntRect(borderBoxRect()));
 
     Color backgroundColor = resolveColor(CSSPropertyBackgroundColor);
     if (backgroundColor.alpha()) {
         paintedExtent = backgroundRect;
         return true;
     }
 
     if (!style()->backgroundLayers().image() || style()->backgroundLayers().next()) {
         paintedExtent =  backgroundRect;
@@ skipping 103 matching lines @@
     return false;
 }
 
 bool LayoutBox::computeBackgroundIsKnownToBeObscured()
 {
     // Test to see if the children trivially obscure the background.
     // FIXME: This test can be much more comprehensive.
     if (!hasBackground())
         return false;
     // Table and root background painting is special.
-    if (isTable() || isDocumentElement())
+    if (isTable() || isLayoutView())
         return false;
     // FIXME: box-shadow is painted while background painting.
     if (style()->boxShadow())
         return false;
     LayoutRect backgroundRect;
     if (!getBackgroundPaintedExtent(backgroundRect))
         return false;
     return foregroundIsKnownToBeOpaqueInRect(backgroundRect, backgroundObscurationTestMaxDepth);
 }
 
@@ skipping 3487 matching lines @@
 bool LayoutBox::canRenderBorderImage() const
 {
     if (!style()->hasBorderDecoration())
         return false;
 
     StyleImage* borderImage = style()->borderImage().image();
     return borderImage && borderImage->canRender(*this, style()->effectiveZoom()) && borderImage->isLoaded();
 }
 
 } // namespace blink