Generate scroll/clip display item hierarchy for SPv2

Source/core/paint/DeprecatedPaintLayer.h

Index: Source/core/paint/DeprecatedPaintLayer.h
diff --git a/Source/core/paint/DeprecatedPaintLayer.h b/Source/core/paint/DeprecatedPaintLayer.h
index a82ca8e54b1c2b9a1d2b03b8c2d918b890d01b34..f060a374cdc90f7c3b73c186189f0b44df3a5c20 100644
--- a/Source/core/paint/DeprecatedPaintLayer.h
+++ b/Source/core/paint/DeprecatedPaintLayer.h
@@ -139,6 +139,10 @@ public:
     }
 
     const LayoutPoint& location() const { ASSERT(!m_needsPositionUpdate); return m_location; }
+    // Note: This function is only needed during the transition period to SPv2.
+    // Once we have eliminated layer-based hit testing and clipping,
+    // we can cache the unscrolled location instead.
+    LayoutPoint locationSansOverflowScroll() const;

[pdr., 2015/08/25 20:47:55]

Super nit: locationWithoutOverflowScroll.

[trchen, 2015/08/26 07:39:04]

Acknowledged. Probably will de-dupe the function and use an enum option instead.

     // FIXME: size() should ASSERT(!m_needsPositionUpdate) as well, but that fails in some tests,
     // for example, fast/repaint/clipped-relative.html.
     const IntSize& size() const { return m_size; }
@@ -224,6 +228,7 @@ public:
     }
 
     void convertToLayerCoords(const DeprecatedPaintLayer* ancestorLayer, LayoutPoint&) const;
+    void convertToLayerCoordsSansOverflowScroll(const DeprecatedPaintLayer* ancestorLayer, LayoutPoint&) const;
     void convertToLayerCoords(const DeprecatedPaintLayer* ancestorLayer, LayoutRect&) const;
 
     // Does the same as convertToLayerCoords() when not in multicol. For multicol, however,
@@ -241,7 +246,7 @@ public:
 
     // Bounding box relative to some ancestor layer. Pass offsetFromRoot if known.
     LayoutRect physicalBoundingBox(const DeprecatedPaintLayer* ancestorLayer, const LayoutPoint* offsetFromRoot = 0) const;
-    LayoutRect physicalBoundingBoxIncludingReflectionAndStackingChildren(const DeprecatedPaintLayer* ancestorLayer, const LayoutPoint& offsetFromRoot) const;
+    LayoutRect physicalBoundingBoxIncludingReflectionAndStackingChildren(const LayoutPoint& offsetFromRoot) const;
     LayoutRect fragmentsBoundingBox(const DeprecatedPaintLayer* ancestorLayer) const;
 
     LayoutRect boundingBoxForCompositingOverlapTest() const;