Fix RTL scroll bars being misrendered on Android.

Source/core/platform/ScrollbarThemeOverlay.cpp

 /*
  * Copyright (C) 2011 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 met:
  *
  * 1.  Redistributions of source code must retain the above copyright
  *     notice, this list of conditions and the following disclaimer.
  * 2.  Redistributions in binary form must reproduce the above copyright
@@ skipping 89 matching lines @@
     if (scrollbar->orientation() == HorizontalScrollbar)
         rect.inflateX(-m_scrollbarMargin);
     else
         rect.inflateY(-m_scrollbarMargin);
     return rect;
 }
 
 void ScrollbarThemeOverlay::paintThumb(GraphicsContext* context, ScrollbarThemeClient* scrollbar, const IntRect& rect)
 {
     IntRect thumbRect = rect;
-    if (scrollbar->orientation() == HorizontalScrollbar)
+    if (scrollbar->orientation() == HorizontalScrollbar) {
         thumbRect.setHeight(thumbRect.height() - m_scrollbarMargin);
-    else
+    } else {
         thumbRect.setWidth(thumbRect.width() - m_scrollbarMargin);
+        if (scrollbar->isLeftSideVerticalScrollbar())
+            thumbRect.setX(thumbRect.x() + m_scrollbarMargin);
+    }
     context->fillRect(thumbRect, m_color);
 }
 
 ScrollbarPart ScrollbarThemeOverlay::hitTest(ScrollbarThemeClient* scrollbar, const IntPoint& position)
 {
     if (m_allowHitTest == DisallowHitTest)
         return NoPart;
 
     return ScrollbarTheme::hitTest(scrollbar, position);
 }
 
 } // namespace WebCore