Fix const correctness of containerForRepaint

Source/core/rendering/RenderObject.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 1317 matching lines @@
     topLevelRect = result;
     for (RenderObject* current = firstChild(); current; current = current->nextSibling())
         current->addAbsoluteRectForLayer(result);
     return result;
 }
 
 void RenderObject::paint(PaintInfo&, const LayoutPoint&)
 {
 }
 
-RenderLayerModelObject* RenderObject::containerForRepaint() const
+const RenderLayerModelObject* RenderObject::containerForRepaint() const
 {
     if (!isRooted())
         return 0;
 
-    RenderLayerModelObject* repaintContainer = 0;
+    const RenderLayerModelObject* repaintContainer = 0;
 
     RenderView* renderView = view();
     if (renderView->usesCompositing()) {
         // FIXME: CompositingState is not necessarily up to date for many callers of this function.
         DisableCompositingQueryAsserts disabler;
 
         if (RenderLayer* compositingLayer = enclosingLayer()->enclosingCompositingLayerForRepaint())
             repaintContainer = compositingLayer->renderer();
     }
 
@@ skipping 88 matching lines @@
 {
     if (!isRooted())
         return;
 
     if (view()->document().printing())
         return; // Don't repaint if we're printing.
 
     // FIXME: really, we're in the repaint phase here, and the following queries are legal.
     // Until those states are fully fledged, I'll just disable the ASSERTS.
     DisableCompositingQueryAsserts disabler;
-    RenderLayerModelObject* repaintContainer = containerForRepaint();
+    const RenderLayerModelObject* repaintContainer = containerForRepaint();
     repaintUsingContainer(repaintContainer, pixelSnappedIntRect(clippedOverflowRectForRepaint(repaintContainer)), InvalidationRepaint);
 }
 
 void RenderObject::repaintRectangle(const LayoutRect& r) const
 {
     if (!isRooted())
         return;
 
     if (view()->document().printing())
         return; // Don't repaint if we're printing.
 
     LayoutRect dirtyRect(r);
 
     if (!RuntimeEnabledFeatures::repaintAfterLayoutEnabled()) {
         // FIXME: layoutDelta needs to be applied in parts before/after transforms and
         // repaint containers. https://bugs.webkit.org/show_bug.cgi?id=23308
         dirtyRect.move(view()->layoutDelta());
     }
 
-    RenderLayerModelObject* repaintContainer = containerForRepaint();
+    const RenderLayerModelObject* repaintContainer = containerForRepaint();
     computeRectForRepaint(repaintContainer, dirtyRect);
     repaintUsingContainer(repaintContainer, pixelSnappedIntRect(dirtyRect), InvalidationRepaintRectangle);
 }
 
 IntRect RenderObject::pixelSnappedAbsoluteClippedOverflowRect() const
 {
     return pixelSnappedIntRect(absoluteClippedOverflowRect());
 }
 
 const char* RenderObject::invalidationReasonToString(InvalidationReason reason) const
@@ skipping 1953 matching lines @@
 {
     if (object1) {
         const WebCore::RenderObject* root = object1;
         while (root->parent())
             root = root->parent();
         root->showRenderTreeAndMark(object1, "*", object2, "-", 0);
     }
 }
 
 #endif