Remove a bit more position:fixed plumbing.

sky/engine/core/rendering/RenderBlock.h

Index: sky/engine/core/rendering/RenderBlock.h
diff --git a/sky/engine/core/rendering/RenderBlock.h b/sky/engine/core/rendering/RenderBlock.h
index f2a5f12bac65801a24e324eb99b155647bf0b9b5..85e8597276c60733f48c0f2c102a383febded07a 100644
--- a/sky/engine/core/rendering/RenderBlock.h
+++ b/sky/engine/core/rendering/RenderBlock.h
@@ -233,12 +233,10 @@ protected:
 
     enum PositionedLayoutBehavior {
         DefaultLayout,
-        LayoutOnlyFixedPositionedObjects,
         ForcedLayoutAfterContainingBlockMoved
     };
 
     void layoutPositionedObjects(bool relayoutChildren, PositionedLayoutBehavior = DefaultLayout);
-    void markFixedPositionObjectForLayoutIfNeeded(RenderObject* child, SubtreeLayoutScope&);
 
     LayoutUnit marginIntrinsicLogicalWidthForChild(RenderBox* child) const;