Code cleanup: Replace Element with Document in element.animate()

third_party/WebKit/Source/core/animation/KeyframeEffect.cpp

Index: third_party/WebKit/Source/core/animation/KeyframeEffect.cpp
diff --git a/third_party/WebKit/Source/core/animation/KeyframeEffect.cpp b/third_party/WebKit/Source/core/animation/KeyframeEffect.cpp
index 5d480edfc656d7ccdf24d6886d5609b8ca6e5a16..488143acad3322fafab3882d91f406c778d53ac4 100644
--- a/third_party/WebKit/Source/core/animation/KeyframeEffect.cpp
+++ b/third_party/WebKit/Source/core/animation/KeyframeEffect.cpp
@@ -56,32 +56,31 @@ KeyframeEffect* KeyframeEffect::create(Element* target, EffectModel* model, cons
 KeyframeEffect* KeyframeEffect::create(ExecutionContext* executionContext, Element* element, const EffectModelOrDictionarySequenceOrDictionary& effectInput, double duration, ExceptionState& exceptionState)
 {
     ASSERT(RuntimeEnabledFeatures::webAnimationsAPIEnabled());
-    if (element)
-        UseCounter::count(element->document(), UseCounter::AnimationConstructorKeyframeListEffectObjectTiming);
+    Document& document = toDocument(*executionContext);

[suzyh_UTC10 (ex-contributor), 2016/07/07 05:59:44]

As above, what happens if the ExecutionContext is not a document or is null?

+    UseCounter::count(document, UseCounter::AnimationConstructorKeyframeListEffectObjectTiming);
     Timing timing;
     if (!TimingInput::convert(duration, timing, exceptionState))
         return nullptr;
-    return create(element, EffectInput::convert(element, effectInput, executionContext, exceptionState), timing);
+    return create(element, EffectInput::convert(document, effectInput, executionContext, exceptionState), timing);
 }
 
 KeyframeEffect* KeyframeEffect::create(ExecutionContext* executionContext, Element* element, const EffectModelOrDictionarySequenceOrDictionary& effectInput, const KeyframeEffectOptions& timingInput, ExceptionState& exceptionState)
 {
     ASSERT(RuntimeEnabledFeatures::webAnimationsAPIEnabled());
-    if (element)
-        UseCounter::count(element->document(), UseCounter::AnimationConstructorKeyframeListEffectObjectTiming);
+    Document& document = toDocument(*executionContext);
+    UseCounter::count(document, UseCounter::AnimationConstructorKeyframeListEffectObjectTiming);
     Timing timing;
-    Document* document = element ? &element->document() : nullptr;
     if (!TimingInput::convert(timingInput, timing, document, exceptionState))
         return nullptr;
-    return create(element, EffectInput::convert(element, effectInput, executionContext, exceptionState), timing);
+    return create(element, EffectInput::convert(document, effectInput, executionContext, exceptionState), timing);
 }
 
 KeyframeEffect* KeyframeEffect::create(ExecutionContext* executionContext, Element* element, const EffectModelOrDictionarySequenceOrDictionary& effectInput, ExceptionState& exceptionState)
 {
     ASSERT(RuntimeEnabledFeatures::webAnimationsAPIEnabled());
-    if (element)
-        UseCounter::count(element->document(), UseCounter::AnimationConstructorKeyframeListEffectNoTiming);
-    return create(element, EffectInput::convert(element, effectInput, executionContext, exceptionState), Timing());
+    Document& document = toDocument(*executionContext);
+    UseCounter::count(document, UseCounter::AnimationConstructorKeyframeListEffectNoTiming);
+    return create(element, EffectInput::convert(document, effectInput, executionContext, exceptionState), Timing());
 }
 
 KeyframeEffect::KeyframeEffect(Element* target, EffectModel* model, const Timing& timing, Priority priority, EventDelegate* eventDelegate)