Revert of Remove RenderLayer::collectFragments.

sky/engine/core/rendering/LayerFragment.h

 /*
  * Copyright (C) 2003, 2009, 2012 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 20 matching lines @@
 
 namespace blink {
 
 struct LayerFragment {
 public:
     LayerFragment()
         : shouldPaintContent(false)
     {
     }
 
+    void setRects(const LayoutRect& bounds, const ClipRect& background, const ClipRect& foreground, const ClipRect& outline)
+    {
+        layerBounds = bounds;
+        backgroundRect = background;
+        foregroundRect = foreground;
+        outlineRect = outline;
+    }
+
+    void moveBy(const LayoutPoint& offset)
+    {
+        layerBounds.moveBy(offset);
+        backgroundRect.moveBy(offset);
+        foregroundRect.moveBy(offset);
+        outlineRect.moveBy(offset);
+    }
+
+    void intersect(const LayoutRect& rect)
+    {
+        backgroundRect.intersect(rect);
+        foregroundRect.intersect(rect);
+        outlineRect.intersect(rect);
+    }
+
     bool shouldPaintContent;
     LayoutRect layerBounds;
     ClipRect backgroundRect;
     ClipRect foregroundRect;
     ClipRect outlineRect;
 };
 
 typedef Vector<LayerFragment, 1> LayerFragments;
 
 } // namespace blink
 
 #endif  // SKY_ENGINE_CORE_RENDERING_LAYERFRAGMENT_H_