Revert of Separate repaint and layout requirements of StyleDifference (Step 1)

Source/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 3779 matching lines @@
 
 void RenderLayer::styleChanged(StyleDifference diff, const RenderStyle* oldStyle)
 {
     m_stackingNode->updateIsNormalFlowOnly();
     m_stackingNode->updateStackingNodesAfterStyleChange(oldStyle);
 
     if (m_scrollableArea)
         m_scrollableArea->updateAfterStyleChange(oldStyle);
 
     if (!oldStyle || oldStyle->visibility() != renderer()->style()->visibility()) {
-        ASSERT(!oldStyle || diff.needsRepaint() || diff.needsLayout());
+        ASSERT(!oldStyle || diff >= StyleDifferenceRepaint);
         compositor()->setNeedsUpdateCompositingRequirementsState();
     }
 
     // Overlay scrollbars can make this layer self-painting so we need
     // to recompute the bit once scrollbars have been updated.
     updateSelfPaintingLayer();
 
     if (!oldStyle || renderer()->style()->position() != oldStyle->position()) {
-        ASSERT(!oldStyle || diff.needsFullLayout());
+        ASSERT(!oldStyle || diff >= StyleDifferenceLayout);
         updateOutOfFlowPositioned(oldStyle);
     }
 
     if (!oldStyle || !renderer()->style()->reflectionDataEquivalent(oldStyle)) {
-        ASSERT(!oldStyle || diff.needsFullLayout());
+        ASSERT(!oldStyle || diff >= StyleDifferenceLayout);
         updateReflectionInfo(oldStyle);
     }
 
     if (RuntimeEnabledFeatures::cssCompositingEnabled())
         m_blendInfo.updateBlendMode();
 
     updateDescendantDependentFlags();
 
     if (!oldStyle || !renderer()->style()->transformDataEquivalent(*oldStyle))
         updateTransform();
@@ skipping 178 matching lines @@
     }
 }
 
 void showLayerTree(const WebCore::RenderObject* renderer)
 {
     if (!renderer)
         return;
     showLayerTree(renderer->enclosingLayer());
 }
 #endif