Clean up stale FIXMEs and TODOs in core/animation

third_party/WebKit/Source/core/animation/css/CSSAnimations.cpp

Index: third_party/WebKit/Source/core/animation/css/CSSAnimations.cpp
diff --git a/third_party/WebKit/Source/core/animation/css/CSSAnimations.cpp b/third_party/WebKit/Source/core/animation/css/CSSAnimations.cpp
index f5f3fc0f9e1ecde24f85d2337b2c1f2f81ea66fa..9de013e0504219538784dd11a15444359931adb5 100644
--- a/third_party/WebKit/Source/core/animation/css/CSSAnimations.cpp
+++ b/third_party/WebKit/Source/core/animation/css/CSSAnimations.cpp
@@ -153,7 +153,7 @@ static StringKeyframeEffectModel* createKeyframeEffectModel(StyleResolver* resol
     DCHECK(!keyframes.first()->offset());
     DCHECK_EQ(keyframes.last()->offset(), 1);
 
-    // FIXME: This is only used for use counting neutral keyframes running on the compositor.
+    // This is used for use counting neutral keyframes running on the compositor.
     PropertySet allProperties;
     for (const auto& keyframe : keyframes) {
         for (const auto& property : keyframe->properties())