Revert r154797: "Move isValid/isCurrentColor from Color to StyleColor"

Source/core/rendering/RenderTreeAsText.cpp

 /*
  * Copyright (C) 2004, 2006, 2007 Apple 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
  *    notice, this list of conditions and the following disclaimer in the
@@ skipping 243 matching lines @@
             ts << " " << quoteAndEscapeNonPrintables(toRenderFileUploadControl(&o)->fileTextValue());
 
         if (o.parent()) {
             Color color = o.resolveColor(CSSPropertyColor);
             if (o.parent()->resolveColor(CSSPropertyColor) != color)
                 ts << " [color=" << color.nameForRenderTreeAsText() << "]";
 
             // Do not dump invalid or transparent backgrounds, since that is the default.
             Color backgroundColor = o.resolveColor(CSSPropertyBackgroundColor);
             if (o.parent()->resolveColor(CSSPropertyBackgroundColor) != backgroundColor
-                && backgroundColor.rgb())
+                && backgroundColor.isValid() && backgroundColor.rgb())
                 ts << " [bgcolor=" << backgroundColor.nameForRenderTreeAsText() << "]";
 
             Color textFillColor = o.resolveColor(CSSPropertyWebkitTextFillColor);
             if (o.parent()->resolveColor(CSSPropertyWebkitTextFillColor) != textFillColor
-                && textFillColor != color && textFillColor.rgb())
+                && textFillColor.isValid() && textFillColor != color && textFillColor.rgb())
                 ts << " [textFillColor=" << textFillColor.nameForRenderTreeAsText() << "]";
 
             Color textStrokeColor = o.resolveColor(CSSPropertyWebkitTextStrokeColor);
             if (o.parent()->resolveColor(CSSPropertyWebkitTextStrokeColor) != textStrokeColor
-                && textStrokeColor != color && textStrokeColor.rgb())
+                && textStrokeColor.isValid() && textStrokeColor != color && textStrokeColor.rgb())
                 ts << " [textStrokeColor=" << textStrokeColor.nameForRenderTreeAsText() << "]";
 
             if (o.parent()->style()->textStrokeWidth() != o.style()->textStrokeWidth() && o.style()->textStrokeWidth() > 0)
                 ts << " [textStrokeWidth=" << o.style()->textStrokeWidth() << "]";
         }
 
         if (!o.isBoxModelObject())
             return;
 
         const RenderBoxModelObject& box = *toRenderBoxModelObject(&o);
@@ skipping 564 matching lines @@
     element->document().updateLayout();
 
     RenderObject* renderer = element->renderer();
     if (!renderer || !renderer->isListItem())
         return String();
 
     return toRenderListItem(renderer)->markerText();
 }
 
 } // namespace WebCore