Simplify animation/transition parsing slightly

Source/core/animation/TimingInput.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 "config.h"
 #include "core/animation/TimingInput.h"
 
 #include "bindings/v8/Dictionary.h"
 #include "core/css/parser/BisonCSSParser.h"
 #include "core/css/resolver/CSSToStyleMap.h"
@@ skipping 71 matching lines @@
         timing.direction = Timing::PlaybackDirectionAlternate;
     } else if (direction == "alternate-reverse") {
         timing.direction = Timing::PlaybackDirectionAlternateReverse;
     } else {
         timing.direction = Timing::defaults().direction;
     }
 }
 
 void TimingInput::setTimingFunction(Timing& timing, const String& timingFunctionString)
 {
-    RefPtrWillBeRawPtr<CSSValue> timingFunctionValue = BisonCSSParser::parseAnimationTimingFunctionValue(timingFunctionString);
-
-    if (timingFunctionValue && !timingFunctionValue->isInitialValue())
+    if (RefPtrWillBeRawPtr<CSSValue> timingFunctionValue = BisonCSSParser::parseAnimationTimingFunctionValue(timingFunctionString))
         timing.timingFunction = CSSToStyleMap::mapAnimationTimingFunction(timingFunctionValue.get(), true);
     else
         timing.timingFunction = Timing::defaults().timingFunction;
 }
 
 Timing TimingInput::convert(const Dictionary& timingInputDictionary)
 {
     Timing result;
 
     // FIXME: This method needs to be refactored to handle invalid
@@ skipping 42 matching lines @@
 }
 
 Timing TimingInput::convert(double duration)
 {
     Timing result;
     setIterationDuration(result, duration);
     return result;
 }
 
 } // namespace WebCore