Web Animations API: Fix Synthetic keyframes + partial keyframes

Source/core/animation/EffectInput.cpp

Index: Source/core/animation/EffectInput.cpp
diff --git a/Source/core/animation/EffectInput.cpp b/Source/core/animation/EffectInput.cpp
index c92a32219ab774b6b853f43e5412a3c68bd9d0cc..1c0aff9a04833b7ef8af2bff6b946a45dddad382 100644
--- a/Source/core/animation/EffectInput.cpp
+++ b/Source/core/animation/EffectInput.cpp
@@ -48,7 +48,7 @@ static bool checkDocumentAndRenderer(Element* element)
     return element->renderer();
 }
 
-PassRefPtrWillBeRawPtr<AnimationEffect> EffectInput::convert(Element* element, const Vector<Dictionary>& keyframeDictionaryVector, bool unsafe)
+PassRefPtrWillBeRawPtr<AnimationEffect> EffectInput::convert(Element* element, const Vector<Dictionary>& keyframeDictionaryVector,  ExceptionState& exceptionState, bool unsafe)
 {
     // FIXME: This test will not be neccessary once resolution of keyframe values occurs at
     // animation application time.
@@ -106,7 +106,13 @@ PassRefPtrWillBeRawPtr<AnimationEffect> EffectInput::convert(Element* element, c
     }
 
     // FIXME: Replace this with code that just parses, when that code is available.
-    return StyleResolver::createKeyframeEffectModel(*element, propertySetVector, keyframes);
+    RefPtrWillBeRawPtr<KeyframeEffectModel> keyframeEffectModel = StyleResolver::createKeyframeEffectModel(*element, propertySetVector, keyframes);
+    if (!keyframeEffectModel->isReplaceOnly()) {
+        exceptionState.throwDOMException(NotSupportedError, "Partial keyframes are not supported.");
+        return nullptr;
+    }
+
+    return keyframeEffectModel;
 }
 
 } // namespace WebCore