Remove some dead code from rendering/ folder

Source/core/rendering/RenderBlock.h

Index: Source/core/rendering/RenderBlock.h
diff --git a/Source/core/rendering/RenderBlock.h b/Source/core/rendering/RenderBlock.h
index 989c9dfea21863d4b8f94e2ddda46dc05624fdac..7a6a336c12e050705a7c5672a6506f840d87848e 100644
--- a/Source/core/rendering/RenderBlock.h
+++ b/Source/core/rendering/RenderBlock.h
@@ -259,8 +259,6 @@ public:
     void showLineTreeAndMark(const InlineBox* = 0, const char* = 0, const InlineBox* = 0, const char* = 0, const RenderObject* = 0) const;
 #endif
 
-    LayoutSize logicalOffsetFromShapeAncestorContainer(const RenderBlock* container) const;
-
     // inline-block elements paint all phases atomically. This function ensures that. Certain other elements
     // (grid items, flex items) require this behavior as well, and this function exists as a helper for them.
     // It is expected that the caller will call this function independent of the value of paintInfo.phase.