Updating custom scrollbar style

Source/core/rendering/RenderBox.cpp

Index: Source/core/rendering/RenderBox.cpp
diff --git a/Source/core/rendering/RenderBox.cpp b/Source/core/rendering/RenderBox.cpp
index c7d0398f693495644bb18eba689f214060f9cc47..7ae553d47c25d146d69fbf9da8592dba8c725331 100644
--- a/Source/core/rendering/RenderBox.cpp
+++ b/Source/core/rendering/RenderBox.cpp
@@ -211,9 +211,10 @@ void RenderBox::styleDidChange(StyleDifference diff, const RenderStyle* oldStyle
         }
     }
 
-    if (isDocumentElement() || isBody())
+    if (isDocumentElement() || isBody()) {

[skobes, 2014/11/07 00:14:00]

Have you tested this scenario with an overflow:scroll div?  We probably need
similar code in RenderLayerScrollableArea.

[MuVen, 2014/11/07 09:46:59]

this part of code is not needed in RenderLayerScrollbableArea as in
updateAfterStyleChange API 

    if (m_hBar)
        m_hBar->styleChanged();
    if (m_vBar)
        m_vBar->styleChanged(); is being called.

         document().view()->recalculateScrollbarOverlayStyle();
-
+        document().view()->recalculateCustomScrollbarStyle();
+    }
     updateShapeOutsideInfoAfterStyleChange(*style(), oldStyle);
     updateGridPositionAfterStyleChange(oldStyle);
 }