Set up scroll and clip parents

Source/core/page/scrolling/ScrollingCoordinator.cpp

Index: Source/core/page/scrolling/ScrollingCoordinator.cpp
diff --git a/Source/core/page/scrolling/ScrollingCoordinator.cpp b/Source/core/page/scrolling/ScrollingCoordinator.cpp
index f603959fbaf09ab8d3fda31954308b855e303edd..88f5b0fe1bc4255d7cac2cef1e52d3b616254e65 100644
--- a/Source/core/page/scrolling/ScrollingCoordinator.cpp
+++ b/Source/core/page/scrolling/ScrollingCoordinator.cpp
@@ -511,6 +511,32 @@ void ScrollingCoordinator::touchEventTargetRectsDidChange(const Document*)
     setTouchEventTargetRects(touchEventTargetRects);
 }
 
+void ScrollingCoordinator::updateScrollParentForLayer(RenderLayer* child, RenderLayer* parent)
+{
+    WebLayer* childWebLayer = scrollingWebLayerForGraphicsLayer(child->layerForScrollChild());
+    if (!childWebLayer)
+        return;
+
+    WebLayer* scrollParentWebLayer = 0;
+    if (parent && parent->backing())
+        scrollParentWebLayer = scrollingWebLayerForGraphicsLayer(parent->backing()->parentForSublayers());
+
+    childWebLayer->setScrollParent(scrollParentWebLayer);
+}
+
+void ScrollingCoordinator::updateClipParentForLayer(RenderLayer* child, RenderLayer* parent)
+{
+    WebLayer* childWebLayer = scrollingWebLayerForGraphicsLayer(child->backing()->graphicsLayer());
+    if (!childWebLayer)
+        return;
+
+    WebLayer* clipParentWebLayer = 0;
+    if (parent && parent->backing())
+        clipParentWebLayer = scrollingWebLayerForGraphicsLayer(parent->backing()->parentForSublayers());
+
+    childWebLayer->setClipParent(clipParentWebLayer);
+}
+
 void ScrollingCoordinator::willDestroyRenderLayer(RenderLayer* layer)
 {
     m_layersWithTouchRects.remove(layer);