Refactor to simplify how layerType is stored on PaintLayers.

third_party/WebKit/Source/core/layout/LayoutBoxModelObject.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 210 matching lines @@
             setChildNeedsLayout();
         if (hadTransform)
             setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation(LayoutInvalidationReason::StyleChange);
         if (!needsLayout()) {
             // FIXME: We should call a specialized version of this function.
             parentLayer->updateLayerPositionsAfterLayout();
         }
     }
 
     if (layer()) {
-        // FIXME: Ideally we shouldn't need this setter but we can't easily infer an overflow-only layer
-        // from the style.
-        layer()->setLayerType(type);
-
         layer()->styleDidChange(diff, oldStyle);
         if (hadLayer && layer()->isSelfPaintingLayer() != layerWasSelfPainting)
             setChildNeedsLayout();
     }
 
     if (oldStyle && wasHorizontalWritingMode != isHorizontalWritingMode()) {
         // Changing the getWritingMode() may change isOrthogonalWritingModeRoot()
         // of children. Make sure all children are marked/unmarked as orthogonal
         // writing-mode roots.
         bool newHorizontalWritingMode = isHorizontalWritingMode();
@@ skipping 873 matching lines @@
     if (rootElementStyle->hasBackground())
         return false;
 
     if (node() != document().firstBodyElement())
         return false;
 
     return true;
 }
 
 } // namespace blink