Split StyleSurroundData::padding into four individual Lengths.

third_party/WebKit/Source/core/layout/LayoutTheme.cpp

 /**
  * This file is part of the theme implementation for form controls in WebCore.
  *
  * Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2012 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 142 matching lines @@
             static_cast<int>(style.BorderLeftWidth())) {
           style.SetBorderLeftWidth(border_box.Left().Value());
           if (border_box.Left().Value())
             style.SetBorderLeftWidth(border_box.Left().Value());
           else
             style.ResetBorderLeft();
         }
 
         // Padding
         LengthBox padding_box = platform_theme_->ControlPadding(
-            part, style.GetFont().GetFontDescription(), style.Padding(),
+            part, style.GetFont().GetFontDescription(), style.PaddingTop(),
+            style.PaddingRight(), style.PaddingBottom(), style.PaddingLeft(),
             style.EffectiveZoom());
-        if (padding_box != style.Padding())
+        if (!style.PaddingEqual(padding_box))
           style.SetPadding(padding_box);
 
         // Whitespace
         if (platform_theme_->ControlRequiresPreWhiteSpace(part))
           style.SetWhiteSpace(EWhiteSpace::kPre);
 
         // Width / Height
         // The width and height here are affected by the zoom.
         // FIXME: Check is flawed, since it doesn't take min-width/max-width
         // into account.
@@ skipping 736 matching lines @@
   // padding - not honored by WinIE, needs to be removed.
   style.ResetPadding();
 
   // border - honored by WinIE, but looks terrible (just paints in the control
   // box and turns off the Windows XP theme)
   // for now, we will not honor it.
   style.ResetBorder();
 }
 
 }  // namespace blink