Fix overflow rect calculation for float in rtl container.

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 309 matching lines @@
 
   using LayoutBoxModelObject::moveChildrenTo;
   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();
-
+    LayoutUnit scrollbarAdjustment(originAdjustmentForScrollbars().width());
+    if (isHorizontalWritingMode()) {
+      return child.x() + child.layoutObject()->marginLeft() +
+             scrollbarAdjustment;
+    }
     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();
@@ skipping 610 matching lines @@
   void positionDialog();
 
   // END METHODS DEFINED IN LayoutBlockFlowLine
 };
 
 DEFINE_LAYOUT_OBJECT_TYPE_CASTS(LayoutBlockFlow, isLayoutBlockFlow());
 
 }  // namespace blink
 
 #endif  // LayoutBlockFlow_h