Re-use CSSParser logic to parse keyframe keys

Source/core/css/CSSKeyframeRule.h

Index: Source/core/css/CSSKeyframeRule.h
diff --git a/Source/core/css/CSSKeyframeRule.h b/Source/core/css/CSSKeyframeRule.h
index c6639b0c73803c03939e5c1877f58fc49caf08ad..1d3332349e7f2365ba96a9155ea84bdbafcc7bd7 100644
--- a/Source/core/css/CSSKeyframeRule.h
+++ b/Source/core/css/CSSKeyframeRule.h
@@ -45,13 +45,14 @@ public:
     }
     ~StyleKeyframe();
 
-    String keyText() const { return m_key; }
-    // FIXME: Should we trim whitespace?
-    // FIXME: Should we leave keyText unchanged when attempting to set to an
-    // invalid string?
-    void setKeyText(const String& s) { m_key = s; }
+    // Exposed to JavaScript.
+    String keyText() const;
+    void setKeyText(const String&);
 
-    void getKeys(Vector<float>& keys) const   { parseKeyString(m_key, keys); }
+    // Used by StyleResolver.
+    const Vector<float>& keys() const;
+    // Used by CSSParser when constructing a new StyleKeyframe.
+    void setKeys(PassOwnPtr<Vector<float> >);
 
     const StylePropertySet* properties() const { return m_properties.get(); }
     MutableStylePropertySet* mutableProperties();
@@ -64,12 +65,10 @@ public:
 private:
     StyleKeyframe();
 
-    static void parseKeyString(const String&, Vector<float>& keys);
-
     RefPtr<StylePropertySet> m_properties;
-    // FIXME: This should be a parsed vector of floats.
-    // comma separated list of keys
-    String m_key;
+    // These are both calculated lazily. Either one can be set, which invalidates the other.
+    mutable String m_keyText;
+    mutable OwnPtr<Vector<float> > m_keys;
 };
 
 class CSSKeyframeRule : public CSSRule {