Adjust constness to avoid const_cast.

third_party/WebKit/Source/core/layout/LayoutObject.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 2999 matching lines @@
     Uncached
 };
 
 static PassRefPtr<ComputedStyle> firstLineStyleForCachedUncachedType(StyleCacheState type, const LayoutObject* layoutObject, ComputedStyle* style)
 {
     const LayoutObject* layoutObjectForFirstLineStyle = layoutObject;
     if (layoutObject->isBeforeOrAfterContent())
         layoutObjectForFirstLineStyle = layoutObject->parent();
 
     if (layoutObjectForFirstLineStyle->canHaveFirstLineOrFirstLetterStyle()) {
-        if (LayoutBlock* firstLineBlock = toLayoutBlock(layoutObjectForFirstLineStyle)->enclosingFirstLineStyleBlock()) {
+        if (const LayoutBlock* firstLineBlock = toLayoutBlock(layoutObjectForFirstLineStyle)->enclosingFirstLineStyleBlock()) {
             if (type == Cached)
                 return firstLineBlock->getCachedPseudoStyle(PseudoIdFirstLine, style);
             return firstLineBlock->getUncachedPseudoStyle(PseudoStyleRequest(PseudoIdFirstLine), style, firstLineBlock == layoutObject ? style : 0);
         }
     } else if (!layoutObjectForFirstLineStyle->isAnonymous() && layoutObjectForFirstLineStyle->isLayoutInline()
         && !layoutObjectForFirstLineStyle->node()->isFirstLetterPseudoElement()) {
         const ComputedStyle* parentStyle = layoutObjectForFirstLineStyle->parent()->firstLineStyle();
         if (parentStyle != layoutObjectForFirstLineStyle->parent()->style()) {
             if (type == Cached) {
                 // A first-line style is in effect. Cache a first-line style for ourselves.
@@ skipping 668 matching lines @@
         const blink::LayoutObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showLayoutTreeAndMark(object1, "*", object2, "-", 0);
     } else {
         fprintf(stderr, "Cannot showLayoutTree. Root is (nil)\n");
     }
 }
 
 #endif