Reduce the number of CachedUAStyles

Source/core/rendering/RenderThemeChromiumMac.mm

 /*
  * Copyright (C) 2005, 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Google, 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.
  *
  * This library is distributed in the hope that it will be useful,
@@ skipping 492 matching lines @@
     }
 
     if (needsFallback)
         color = RenderTheme::systemColor(cssValueId);
 
     m_systemColorCache.set(cssValueId, color.rgb());
 
     return color;
 }
 
-bool RenderThemeChromiumMac::isControlStyled(const RenderStyle* style, const CachedUAStyle& uaStyle) const
+bool RenderThemeChromiumMac::isControlStyled(const RenderStyle* style, const CachedUAStyle* uaStyle) const
 {
+    ASSERT(uaStyle);
     if (style->appearance() == TextFieldPart || style->appearance() == TextAreaPart || style->appearance() == ListboxPart)
-        return style->border() != uaStyle.border || style->boxShadow();
+        return style->border() != uaStyle->border || style->boxShadow();
 
     // FIXME: This is horrible, but there is not much else that can be done.  Menu lists cannot draw properly when
     // scaled.  They can't really draw properly when transformed either.  We can't detect the transform case at style
     // adjustment time so that will just have to stay broken.  We can however detect that we're zooming.  If zooming
     // is in effect we treat it like the control is styled.
     if (style->appearance() == MenulistPart && style->effectiveZoom() != 1.0f)
         return true;
     // FIXME: NSSearchFieldCell doesn't work well when scaled.
     if (style->appearance() == SearchFieldPart && style->effectiveZoom() != 1)
         return true;
@@ skipping 1377 matching lines @@
 
 bool RenderThemeChromiumMac::shouldUseFallbackTheme(RenderStyle* style) const
 {
     ControlPart part = style->appearance();
     if (part == CheckboxPart || part == RadioPart)
         return style->effectiveZoom() != 1;
     return false;
 }
 
 } // namespace WebCore