Refactor BlendMode into a separate class.

Source/core/rendering/RenderLayerCompositor.cpp

 /*
  * Copyright (C) 2009, 2010 Apple Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 960 matching lines @@
     if (layer->reflectionInfo()) {
         // FIXME: Shouldn't we call computeCompositingRequirements to handle a reflection overlapping with another renderer?
         CompositingReasons reflectionCompositingReason = willBeComposited ? CompositingReasonReflectionOfCompositedParent : CompositingReasonNone;
         layer->reflectionInfo()->reflectionLayer()->setCompositingReasons(layer->reflectionInfo()->reflectionLayer()->compositingReasons() | reflectionCompositingReason);
     }
 
     // Subsequent layers in the parent's stacking context may also need to composite.
     if (childRecursionData.m_subtreeIsCompositing)
         currentRecursionData.m_subtreeIsCompositing = true;
 
-    if (willBeComposited && layer->hasBlendMode())
+    if (willBeComposited && layer->blendInfo().hasBlendMode())
         currentRecursionData.m_hasUnisolatedCompositedBlendingDescendant = true;
 
     // Set the flag to say that this SC has compositing children.
     layer->setHasCompositingDescendant(childRecursionData.m_subtreeIsCompositing);
 
     // Turn overlap testing off for later layers if it's already off, or if we have an animating transform.
     // Note that if the layer clips its descendants, there's no reason to propagate the child animation to the parent layers. That's because
     // we know for sure the animation is contained inside the clipping rectangle, which is already added to the overlap map.
     bool isCompositedClippingLayer = canBeComposited(layer) && (reasonsToComposite & CompositingReasonClipsCompositingDescendants);
     if ((!childRecursionData.m_testingOverlap && !isCompositedClippingLayer) || isRunningAcceleratedTransformAnimation(layer->renderer()))
@@ skipping 1596 matching lines @@
     } else if (graphicsLayer == m_scrollLayer.get()) {
         name = "Frame Scrolling Layer";
     } else {
         ASSERT_NOT_REACHED();
     }
 
     return name;
 }
 
 } // namespace WebCore