Generate toCSSFooValue for CSS*GradientValues

Source/core/css/CSSGradientValue.h

Index: Source/core/css/CSSGradientValue.h
diff --git a/Source/core/css/CSSGradientValue.h b/Source/core/css/CSSGradientValue.h
index 75e51520a94fa585304e913c64213d77d19be1c4..1429e5008e9a651dee0830658c5f7a786da8f0ff 100644
--- a/Source/core/css/CSSGradientValue.h
+++ b/Source/core/css/CSSGradientValue.h
@@ -75,9 +75,6 @@ public:
 
     void sortStopsIfNeeded();
 
-    bool isLinearGradient() const { return classType() == LinearGradientClass; }
-    bool isRadialGradient() const { return classType() == RadialGradientClass; }
-
     bool isRepeating() const { return m_repeating; }
 
     CSSGradientType gradientType() const { return m_gradientType; }
@@ -134,6 +131,7 @@ protected:
     bool m_repeating;
 };
 
+DEFINE_CSS_VALUE_TYPE_CASTS(GradientValue);
 
 class CSSLinearGradientValue : public CSSGradientValue {
 public:
@@ -172,6 +170,8 @@ private:
     RefPtr<CSSPrimitiveValue> m_angle; // may be null.
 };
 
+DEFINE_CSS_VALUE_TYPE_CASTS(LinearGradientValue);
+
 class CSSRadialGradientValue : public CSSGradientValue {
 public:
     static PassRefPtr<CSSRadialGradientValue> create(CSSGradientRepeat repeat, CSSGradientType gradientType = CSSRadialGradient)
@@ -233,6 +233,8 @@ private:
     RefPtr<CSSPrimitiveValue> m_endVerticalSize;
 };
 
+DEFINE_CSS_VALUE_TYPE_CASTS(RadialGradientValue);
+
 } // namespace WebCore
 
 #endif // CSSGradientValue_h