C++11: Replace 0 with nullptr where applicable in layout code.

Source/core/layout/LayoutListItem.cpp

 /**
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  * Copyright (C) 2003, 2004, 2005, 2006, 2010 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Andrew Wellington (proton@wiretapped.net)
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
@@ skipping 111 matching lines @@
             firstNode = parent;
     }
 
     // If there's no actual <ul> or <ol> list element, then the first found
     // node acts as our list for purposes of determining what other list items
     // should be numbered as part of the same list.
     return firstNode;
 }
 
 // Returns the next list item with respect to the DOM order.
-static LayoutListItem* nextListItem(const Node* listNode, const LayoutListItem* item = 0)
+static LayoutListItem* nextListItem(const Node* listNode, const LayoutListItem* item = nullptr)
 {
     if (!listNode)
-        return 0;
+        return nullptr;
 
     const Node* current = item ? item->node() : listNode;
     ASSERT(current);
     ASSERT(!current->document().childNeedsDistributionRecalc());
     current = LayoutTreeBuilderTraversal::next(*current, listNode);
 
     while (current) {
         if (isList(*current)) {
             // We've found a nested, independent list: nothing to do here.
             current = LayoutTreeBuilderTraversal::nextSkippingChildren(*current, listNode);
             continue;
         }
 
         LayoutObject* layoutObject = current->layoutObject();
         if (layoutObject && layoutObject->isListItem())
             return toLayoutListItem(layoutObject);
 
         // FIXME: Can this be optimized to skip the children of the elements without a layoutObject?
         current = LayoutTreeBuilderTraversal::next(*current, listNode);
     }
 
-    return 0;
+    return nullptr;
 }
 
 // Returns the previous list item with respect to the DOM order.
 static LayoutListItem* previousListItem(const Node* listNode, const LayoutListItem* item)
 {
     Node* current = item->node();
     ASSERT(current);
     ASSERT(!current->document().childNeedsDistributionRecalc());
     for (current = LayoutTreeBuilderTraversal::previous(*current, listNode); current && current != listNode; current = LayoutTreeBuilderTraversal::previous(*current, listNode)) {
         LayoutObject* layoutObject = current->layoutObject();
         if (!layoutObject || (layoutObject && !layoutObject->isListItem()))
             continue;
         Node* otherList = enclosingList(toLayoutListItem(layoutObject));
         // This item is part of our current list, so it's what we're looking for.
         if (listNode == otherList)
             return toLayoutListItem(layoutObject);
         // We found ourself inside another list; lets skip the rest of it.
         // Use nextIncludingPseudo() here because the other list itself may actually
         // be a list item itself. We need to examine it, so we do this to counteract
         // the previousIncludingPseudo() that will be done by the loop.
         if (otherList)
             current = LayoutTreeBuilderTraversal::next(*otherList, listNode);
     }
-    return 0;
+    return nullptr;
 }
 
 void LayoutListItem::updateItemValuesForOrderedList(const HTMLOListElement* listNode)
 {
     ASSERT(listNode);
 
     for (LayoutListItem* listItem = nextListItem(listNode); listItem; listItem = nextListItem(listNode, listItem))
         listItem->updateValue();
 }
 
@@ skipping 38 matching lines @@
 
 bool LayoutListItem::isEmpty() const
 {
     return lastChild() == m_marker;
 }
 
 static LayoutObject* getParentOfFirstLineBox(LayoutBlockFlow* curr, LayoutObject* marker)
 {
     LayoutObject* firstChild = curr->firstChild();
     if (!firstChild)
-        return 0;
+        return nullptr;
 
     bool inQuirksMode = curr->document().inQuirksMode();
     for (LayoutObject* currChild = firstChild; currChild; currChild = currChild->nextSibling()) {
         if (currChild == marker)
             continue;
 
         if (currChild->isInline() && (!currChild->isLayoutInline() || curr->generatesLineBoxesForInlineChild(currChild)))
             return curr;
 
         if (currChild->isFloating() || currChild->isOutOfFlowPositioned())
             continue;
 
         if (!currChild->isLayoutBlockFlow() || (currChild->isBox() && toLayoutBox(currChild)->isWritingModeRoot()))
             break;
 
         if (curr->isListItem() && inQuirksMode && currChild->node()
             && (isHTMLUListElement(*currChild->node()) || isHTMLOListElement(*currChild->node())))
             break;
 
         LayoutObject* lineBox = getParentOfFirstLineBox(toLayoutBlockFlow(currChild), marker);
         if (lineBox)
             return lineBox;
     }
 
-    return 0;
+    return nullptr;
 }
 
 void LayoutListItem::updateValue()
 {
     if (!m_hasExplicitValue) {
         m_isValueUpToDate = false;
         if (m_marker)
             m_marker->setNeedsLayoutAndPrefWidthsRecalcAndFullPaintInvalidation(LayoutInvalidationReason::ListValueChange);
     }
 }
@@ skipping 222 matching lines @@
             // assume that all the following ones have too.
             // This gives us the opportunity to stop here and avoid
             // marking the same nodes again.
             break;
         }
         item->updateValue();
     }
 }
 
 } // namespace blink