Throw TypeError if easing string is invalid.

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

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/animation/KeyframeEffect.h"
 
 #include "bindings/core/v8/Dictionary.h"
 #include "bindings/core/v8/UnionTypesCore.h"
 #include "bindings/core/v8/V8BindingForTesting.h"
 #include "bindings/core/v8/V8KeyframeEffectOptions.h"
@@ skipping 218 matching lines @@
 
     EXPECT_EQ(1, specified->playbackRate());
     specified->setPlaybackRate(2);
     EXPECT_EQ(2, specified->playbackRate());
 
     EXPECT_EQ("normal", specified->direction());
     specified->setDirection("reverse");
     EXPECT_EQ("reverse", specified->direction());
 
     EXPECT_EQ("linear", specified->easing());
-    specified->setEasing("step-start");
+    specified->setEasing("step-start", exceptionState);
+    ASSERT_FALSE(exceptionState.hadException());
     EXPECT_EQ("step-start", specified->easing());
 }
 
 TEST_F(AnimationKeyframeEffectV8Test, SetSpecifiedDuration)
 {
     Vector<Dictionary, 0> jsKeyframes;
     v8::Local<v8::Object> timingInput = v8::Object::New(m_isolate);
     KeyframeEffectOptions timingInputDictionary;
     V8KeyframeEffectOptions::toImpl(m_isolate, timingInput, timingInputDictionary, exceptionState);
     KeyframeEffect* animation = createAnimation(element.get(), jsKeyframes, timingInputDictionary, exceptionState);
@@ skipping 120 matching lines @@
     Timing timing;
     timing.iterationDuration = 5;
     KeyframeEffect* animation = KeyframeEffect::create(element.get(), nullptr, timing);
     EXPECT_EQ(element.get(), animation->target());
     document().timeline().play(animation);
     pageHolder.clear();
     element.clear();
 }
 
 } // namespace blink