Move isValid/isCurrentColor from Color to StyleColor

Source/core/rendering/style/StyleRareInheritedData.h

Index: Source/core/rendering/style/StyleRareInheritedData.h
diff --git a/Source/core/rendering/style/StyleRareInheritedData.h b/Source/core/rendering/style/StyleRareInheritedData.h
index 1640c30cf34f948e3b7669bd510eb7769a812f64..8d914e3661ed7310f48a6b52b4085898e2fc04fe 100644
--- a/Source/core/rendering/style/StyleRareInheritedData.h
+++ b/Source/core/rendering/style/StyleRareInheritedData.h
@@ -25,8 +25,8 @@
 #ifndef StyleRareInheritedData_h
 #define StyleRareInheritedData_h
 
+#include "core/css/StyleColor.h"
 #include "core/platform/Length.h"
-#include "core/platform/graphics/Color.h"
 #include <wtf/PassRefPtr.h>
 #include <wtf/RefCounted.h>
 #include <wtf/text/AtomicString.h>
@@ -59,14 +59,14 @@ public:
 
     RefPtr<StyleImage> listStyleImage;
 
-    Color textStrokeColor;
+    StyleColor textStrokeColor;
     float textStrokeWidth;
-    Color textFillColor;
-    Color textEmphasisColor;
+    StyleColor textFillColor;
+    StyleColor textEmphasisColor;
 
-    Color visitedLinkTextStrokeColor;
-    Color visitedLinkTextFillColor;
-    Color visitedLinkTextEmphasisColor;
+    StyleColor visitedLinkTextStrokeColor;
+    StyleColor visitedLinkTextFillColor;
+    StyleColor visitedLinkTextEmphasisColor;
 
     OwnPtr<ShadowData> textShadow; // Our text shadow information for shadowed text drawing.
     AtomicString highlight; // Apple-specific extension for custom highlight rendering.
@@ -121,7 +121,7 @@ public:
     AtomicString m_lineGrid;
     unsigned m_tabSize;
 
-    Color tapHighlightColor;
+    StyleColor tapHighlightColor;
 
     DataRef<StyleVariableData> m_variables;