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

Source/web/WebViewImpl.cpp

 /*
  * Copyright (C) 2011, 2012 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:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 1224 matching lines @@
 void WebViewImpl::enableTapHighlight(const PlatformGestureEvent& tapEvent)
 {
     // Always clear any existing highlight when this is invoked, even if we don't get a new target to highlight.
     m_linkHighlight.clear();
 
     Node* touchNode = bestTapNode(tapEvent);
 
     if (!touchNode || !touchNode->renderer() || !touchNode->renderer()->enclosingLayer())
         return;
 
-    Color highlightColor = touchNode->renderer()->resolveColor(CSSPropertyWebkitTapHighlightColor);
+    Color highlightColor = touchNode->renderer()->style()->tapHighlightColor();
     // Safari documentation for -webkit-tap-highlight-color says if the specified color has 0 alpha,
     // then tap highlighting is disabled.
     // http://developer.apple.com/library/safari/#documentation/appleapplications/reference/safaricssref/articles/standardcssproperties.html
     if (!highlightColor.alpha())
         return;
 
     m_linkHighlight = LinkHighlight::create(touchNode, this);
 }
 
 void WebViewImpl::animateDoubleTapZoom(const IntPoint& point)
@@ skipping 1144 matching lines @@
     return false;
 }
 
 WebColor WebViewImpl::backgroundColor() const
 {
     if (isTransparent())
         return Color::transparent;
     if (!m_page)
         return m_baseBackgroundColor;
     FrameView* view = m_page->mainFrame()->view();
-    StyleColor backgroundColor = view->documentBackgroundColor();
+    Color backgroundColor = view->documentBackgroundColor();
     if (!backgroundColor.isValid())
         return m_baseBackgroundColor;
     return backgroundColor.rgb();
 }
 
 bool WebViewImpl::caretOrSelectionRange(size_t* location, size_t* length)
 {
     const Frame* focused = focusedWebCoreFrame();
     if (!focused)
         return false;
@@ skipping 1684 matching lines @@
 }
 
 bool WebViewImpl::shouldDisableDesktopWorkarounds()
 {
     ViewportArguments arguments = mainFrameImpl()->frame()->document()->viewportArguments();
     return arguments.width == ViewportArguments::ValueDeviceWidth || !arguments.userZoom
         || (arguments.minZoom == arguments.maxZoom && arguments.minZoom != ViewportArguments::ValueAuto);
 }
 
 } // namespace WebKit