Fix zero height root renderer with background image painting

Source/core/rendering/RenderBoxModelObject.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 Apple Inc. All rights reserved.
  * Copyright (C) 2010 Google Inc. 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 646 matching lines @@
         }
         view()->frameView()->setContentIsOpaque(isOpaqueRoot);
     }
 
     // Paint the color first underneath all images, culled if background image occludes it.
     // FIXME: In the bgLayer->hasFiniteBounds() case, we could improve the culling test
     // by verifying whether the background image covers the entire layout rect.
     if (!bgLayer->next()) {
         IntRect backgroundRect(pixelSnappedIntRect(scrolledPaintRect));
         bool boxShadowShouldBeAppliedToBackground = this->boxShadowShouldBeAppliedToBackground(bleedAvoidance, box);
-        if (boxShadowShouldBeAppliedToBackground || !shouldPaintBackgroundImage || !bgLayer->hasOpaqueImage(this) || !bgLayer->hasRepeatXY()) {
+        if (boxShadowShouldBeAppliedToBackground || !shouldPaintBackgroundImage || !bgLayer->hasOpaqueImage(this) || !bgLayer->hasRepeatXY() || (isOpaqueRoot && !toRenderBox(this)->height()))  {
             if (!boxShadowShouldBeAppliedToBackground)
                 backgroundRect.intersect(paintInfo.rect);
 
             GraphicsContextStateSaver shadowStateSaver(*context, boxShadowShouldBeAppliedToBackground);
             if (boxShadowShouldBeAppliedToBackground)
                 applyBoxShadowForBackground(context, this);
 
             if (isOpaqueRoot) {
                 // If we have an alpha and we are painting the root element, go ahead and blend with the base background color.
                 Color baseColor = view()->frameView()->baseBackgroundColor();
@@ skipping 2131 matching lines @@
     ASSERT(!beforeChild || toBoxModelObject == beforeChild->parent());
     for (RenderObject* child = startChild; child && child != endChild; ) {
         // Save our next sibling as moveChildTo will clear it.
         RenderObject* nextSibling = child->nextSibling();
         moveChildTo(toBoxModelObject, child, beforeChild, fullRemoveInsert);
         child = nextSibling;
     }
 }
 
 } // namespace WebCore