Remove viewportDefiningElement.

sky/engine/core/rendering/RenderLayerScrollableArea.cpp

Index: sky/engine/core/rendering/RenderLayerScrollableArea.cpp
diff --git a/sky/engine/core/rendering/RenderLayerScrollableArea.cpp b/sky/engine/core/rendering/RenderLayerScrollableArea.cpp
index 37bf7b37d2abfaacb81f4a88fd5ae96f8ffb51ab..09f67f807e9011544fc1ba900c4b1a470120e135 100644
--- a/sky/engine/core/rendering/RenderLayerScrollableArea.cpp
+++ b/sky/engine/core/rendering/RenderLayerScrollableArea.cpp
@@ -440,21 +440,8 @@ static bool overflowDefinesAutomaticScrollbar(EOverflow overflow)
     return overflow == OAUTO || overflow == OOVERLAY;
 }
 
-// This function returns true if the given box requires overflow scrollbars (as
-// opposed to the 'viewport' scrollbars managed by the RenderLayerCompositor).
-// FIXME: we should use the same scrolling machinery for both the viewport and
-// overflow. Currently, we need to avoid producing scrollbars here if they'll be
-// handled externally in the RLC.
-static bool canHaveOverflowScrollbars(const RenderBox& box)
-{
-    return !box.isRenderView() && box.document().viewportDefiningElement() != box.node();
-}
-
 void RenderLayerScrollableArea::updateAfterStyleChange(const RenderStyle* oldStyle)
 {
-    if (!canHaveOverflowScrollbars(box()))
-        return;
-
     if (!m_scrollDimensionsDirty)
         updateScrollableAreaSet(hasScrollableHorizontalOverflow() || hasScrollableVerticalOverflow());