Use nullptr_t for RefPtr, PassRefPtr and RawPtr.

Source/core/frame/FrameView.cpp

 /*
  * Copyright (C) 1998, 1999 Torben Weis <weis@kde.org>
  *                     1999 Lars Knoll <knoll@kde.org>
  *                     1999 Antti Koivisto <koivisto@kde.org>
  *                     2000 Dirk Mueller <mueller@kde.org>
  * Copyright (C) 2004, 2005, 2006, 2007, 2008 Apple Inc. All rights reserved.
  *           (C) 2006 Graham Dennis (graham.dennis@gmail.com)
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
@@ skipping 168 matching lines @@
 
     setHasHorizontalScrollbar(false); // Remove native scrollbars now before we lose the connection to the HostWindow.
     setHasVerticalScrollbar(false);
 
     ASSERT(!m_scrollCorner);
 
     ASSERT(m_frame);
     ASSERT(m_frame->view() != this || !m_frame->contentRenderer());
     RenderPart* renderer = m_frame->ownerRenderer();
     if (renderer && renderer->widget() == this)
-        renderer->setWidget(0);
+        renderer->setWidget(nullptr);
 }
 
 void FrameView::reset()
 {
     m_cannotBlitToWindow = false;
     m_isOverlapped = false;
     m_contentIsOpaque = false;
     m_hasPendingLayout = false;
     m_layoutSubtreeRoot = 0;
     m_doFullRepaint = false;
@@ skipping 14 matching lines @@
     m_lastZoomFactor = 1.0f;
     m_isTrackingRepaints = false;
     m_trackedRepaintRects.clear();
     m_lastPaintTime = 0;
     m_paintBehavior = PaintBehaviorNormal;
     m_isPainting = false;
     m_visuallyNonEmptyCharacterCount = 0;
     m_visuallyNonEmptyPixelCount = 0;
     m_isVisuallyNonEmpty = false;
     m_firstVisuallyNonEmptyLayoutCallbackPending = true;
-    m_maintainScrollPositionAnchor = 0;
+    m_maintainScrollPositionAnchor = nullptr;
     m_partialLayout.reset();
     m_viewportConstrainedObjects.clear();
 }
 
 void FrameView::removeFromAXObjectCache()
 {
     if (AXObjectCache* cache = axObjectCache())
         cache->remove(this);
 }
 
@@ skipping 1367 matching lines @@
 
     LayoutRect bounds = element->boundingBox();
     int centeringOffsetX = (rect.width() - bounds.width()) / 2;
     int centeringOffsetY = (rect.height() - bounds.height()) / 2;
     setScrollPosition(IntPoint(bounds.x() - centeringOffsetX - rect.x(), bounds.y() - centeringOffsetY - rect.y()));
 }
 
 void FrameView::setScrollPosition(const IntPoint& scrollPoint)
 {
     TemporaryChange<bool> changeInProgrammaticScroll(m_inProgrammaticScroll, true);
-    m_maintainScrollPositionAnchor = 0;
+    m_maintainScrollPositionAnchor = nullptr;
 
     IntPoint newScrollPosition = adjustScrollPositionWithinRange(scrollPoint);
 
     if (newScrollPosition == scrollPosition())
         return;
 
     ScrollView::setScrollPosition(newScrollPosition);
 }
 
 void FrameView::setScrollPositionNonProgrammatically(const IntPoint& scrollPoint)
@@ skipping 1012 matching lines @@
 
 bool FrameView::wasScrolledByUser() const
 {
     return m_wasScrolledByUser;
 }
 
 void FrameView::setWasScrolledByUser(bool wasScrolledByUser)
 {
     if (m_inProgrammaticScroll)
         return;
-    m_maintainScrollPositionAnchor = 0;
+    m_maintainScrollPositionAnchor = nullptr;
     m_wasScrolledByUser = wasScrolledByUser;
 }
 
 void FrameView::paintContents(GraphicsContext* p, const IntRect& rect)
 {
     Document* document = m_frame->document();
 
 #ifndef NDEBUG
     bool fillWithRed;
     if (document->printing())
@@ skipping 551 matching lines @@
 void FrameView::willRemoveScrollbar(Scrollbar* scrollbar, ScrollbarOrientation orientation)
 {
     ScrollableArea::willRemoveScrollbar(scrollbar, orientation);
     if (AXObjectCache* cache = axObjectCache()) {
         cache->remove(scrollbar);
         cache->handleScrollbarUpdate(this);
     }
 }
 
 } // namespace WebCore