Remove some dead code from rendering/ folder

Source/core/rendering/style/KeyframeList.cpp

Index: Source/core/rendering/style/KeyframeList.cpp
diff --git a/Source/core/rendering/style/KeyframeList.cpp b/Source/core/rendering/style/KeyframeList.cpp
index 2ed58360ee1f8542bfb6e6bfe7e774503605ef81..409a2d8b2cacf585d8290f04414bd63a5655b48f 100644
--- a/Source/core/rendering/style/KeyframeList.cpp
+++ b/Source/core/rendering/style/KeyframeList.cpp
@@ -28,20 +28,6 @@
 
 namespace WebCore {
 
-void KeyframeValue::addProperties(const StylePropertySet* propertySet)
-{
-    if (!propertySet)
-        return;
-    unsigned propertyCount = propertySet->propertyCount();
-    for (unsigned i = 0; i < propertyCount; ++i) {
-        CSSPropertyID property = propertySet->propertyAt(i).id();
-        // Timing-function within keyframes is special, because it is not animated; it just
-        // describes the timing function between this keyframe and the next.
-        if (property != CSSPropertyWebkitAnimationTimingFunction && property != CSSPropertyAnimationTimingFunction)
-            addProperty(property);
-    }
-}
-
 TimingFunction* KeyframeValue::timingFunction(const RenderStyle& keyframeStyle)
 {
     const CSSAnimationDataList* animations = keyframeStyle.animations();