First pass at deleting paint invalidation code.

sky/engine/core/rendering/RenderLayer.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011, 2012 Apple Inc. All rights reserved.
  *
  * Portions are Copyright (C) 1998 Netscape Communications Corporation.
  *
  * Other contributors:
  *   Robert O'Callahan <roc+@cs.cmu.edu>
  *   David Baron <dbaron@fas.harvard.edu>
  *   Christian Biesinger <cbiesinger@web.de>
  *   Randall Jesup <rjesup@wgate.com>
@@ skipping 694 matching lines @@
     return oldChild;
 }
 
 void RenderLayer::removeOnlyThisLayer()
 {
     if (!m_parent)
         return;
 
     m_clipper.clearClipRectsIncludingDescendants();
 
-    paintInvalidator().paintInvalidationIncludingNonCompositingDescendants();
-
     RenderLayer* nextSib = nextSibling();
 
     // Now walk our kids and reattach them to our parent.
     RenderLayer* current = m_first;
     while (current) {
         RenderLayer* next = current->nextSibling();
         removeChild(current);
         m_parent->addChild(current, nextSib);
 
         current->renderer()->setShouldDoFullPaintInvalidation(true);
@@ skipping 1328 matching lines @@
     }
 }
 
 void showLayerTree(const blink::RenderObject* renderer)
 {
     if (!renderer)
         return;
     showLayerTree(renderer->enclosingLayer());
 }
 #endif