Use outlineBox if we have an outline or shadow

Source/core/rendering/RenderObject.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2000 Dirk Mueller (mueller@kde.org)
  *           (C) 2004 Allan Sandfeld Jensen (kde@carewolf.com)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2009 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
  * This library is free software; you can redistribute it and/or
@@ skipping 1496 matching lines @@
         // If a border-radius exists and width/height is smaller than
         // radius width/height, we cannot use delta-repaint.
         RoundedRect oldRoundedRect = style()->getRoundedBorderFor(oldBounds);
         RoundedRect newRoundedRect = style()->getRoundedBorderFor(newBounds);
         fullRepaint = oldRoundedRect.radii() != newRoundedRect.radii();
     }
     if (!fullRepaint) {
         // This ASSERT fails due to animations.  See https://bugs.webkit.org/show_bug.cgi?id=37048
         // ASSERT(!newOutlineBoxRectPtr || *newOutlineBoxRectPtr == outlineBoundsForRepaint(repaintContainer));
         newOutlineBox = newOutlineBoxRectPtr ? *newOutlineBoxRectPtr : outlineBoundsForRepaint(repaintContainer);
-        if (newOutlineBox.location() != oldOutlineBox.location() || (mustRepaintBackgroundOrBorder() && (newBounds != oldBounds || newOutlineBox != oldOutlineBox)))
+
+        bool hasOutlineBox = hasOutline() || (style()->boxShadow() && style()->boxShadow()->shadows().size() > 0);
+        if ((hasOutlineBox && newOutlineBox.location() != oldOutlineBox.location())
+            || (mustRepaintBackgroundOrBorder() && (newBounds != oldBounds || (hasOutlineBox && newOutlineBox != oldOutlineBox))))

[eseidel, 2014/03/05 22:09:41]

You already check hasOutlineBox and location != location.  If that's true, then
this later one must be true.  This seems uneeded.

[dsinclair, 2014/03/05 22:15:06]

If the location's are equal that doesn't mean that the sizes can't be different.
Possibly I should split this to be a nested if to make it easier to read?

If the locations are the same we won't do the second comparison.

             fullRepaint = true;
     }
 
     if (!repaintContainer)
         repaintContainer = v;
 
     if (fullRepaint) {
         repaintUsingContainer(repaintContainer, pixelSnappedIntRect(oldBounds));
         if (newBounds != oldBounds)
             repaintUsingContainer(repaintContainer, pixelSnappedIntRect(newBounds));
@@ skipping 1825 matching lines @@
 {
     if (object1) {
         const WebCore::RenderObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showRenderTreeAndMark(object1, "*", object2, "-", 0);
     }
 }
 
 #endif