Add DISABLE_CFI_PERF attribute on the methods with CFI checks disabled.

third_party/WebKit/Source/core/layout/LayoutBlockFlow.h

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2007 David Smith (catfish.man@gmail.com)
  * Copyright (C) 2003-2013 Apple Inc. All rights reserved.
  * Copyright (C) Research In Motion Limited 2010. All rights reserved.
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
@@ skipping 244 matching lines @@
     void moveChildrenTo(LayoutBoxModelObject* toBoxModelObject, LayoutObject* startChild, LayoutObject* endChild, LayoutObject* beforeChild, bool fullRemoveInsert = false) override;
 
     LayoutUnit xPositionForFloatIncludingMargin(const FloatingObject& child) const
     {
         if (isHorizontalWritingMode())
             return child.x() + child.layoutObject()->marginLeft();
 
         return child.x() + marginBeforeForChild(*child.layoutObject());
     }
 
+    DISABLE_CFI_PERF
     LayoutUnit yPositionForFloatIncludingMargin(const FloatingObject& child) const
     {
         if (isHorizontalWritingMode())
             return child.y() + marginBeforeForChild(*child.layoutObject());
 
         return child.y() + child.layoutObject()->marginTop();
     }
 
     LayoutPoint flipFloatForWritingModeForChild(const FloatingObject&, const LayoutPoint&) const;
 
@@ skipping 383 matching lines @@
 
 // END METHODS DEFINED IN LayoutBlockFlowLine
 
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutBlockFlow, isLayoutBlockFlow());
 
 } // namespace blink
 
 #endif // LayoutBlockFlow_h