Use outlineBox if we have an outline or shadow

Source/core/rendering/RenderObject.cpp

Index: Source/core/rendering/RenderObject.cpp
diff --git a/Source/core/rendering/RenderObject.cpp b/Source/core/rendering/RenderObject.cpp
index fad82562adb24917ac6240b8338ad0156fabbec1..34929b7d2e1b94874c1e1da8399f2f90461a9724 100644
--- a/Source/core/rendering/RenderObject.cpp
+++ b/Source/core/rendering/RenderObject.cpp
@@ -1514,7 +1514,10 @@ bool RenderObject::repaintAfterLayoutIfNeeded(const RenderLayerModelObject* repa
         // 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;
     }