[Blink] Adding Writing direction to the context menu for Aura.

Source/core/platform/ScrollView.h

Index: Source/core/platform/ScrollView.h
diff --git a/Source/core/platform/ScrollView.h b/Source/core/platform/ScrollView.h
index 2fe86daf1a4275d9afa92cb6fa9d5a61e7c3f200..c2069e27e203771b8a52a1495133b7361e05c5a5 100644
--- a/Source/core/platform/ScrollView.h
+++ b/Source/core/platform/ScrollView.h
@@ -93,6 +93,7 @@ public:
     bool horizontalScrollbarLock() const { return m_horizontalScrollbarLock; }
     void setVerticalScrollbarLock(bool lock = true) { m_verticalScrollbarLock = lock; }
     bool verticalScrollbarLock() const { return m_verticalScrollbarLock; }
+    int verticalScrollbarWidth() const { return verticalScrollbar() ? verticalScrollbar()->width() : 0; }
 
     void setScrollingModesLock(bool lock = true) { m_horizontalScrollbarLock = m_verticalScrollbarLock = lock; }