Web Animations: Handle iteration values which overflow int.

Source/core/animation/InertEffect.cpp

Index: Source/core/animation/InertEffect.cpp
diff --git a/Source/core/animation/InertEffect.cpp b/Source/core/animation/InertEffect.cpp
index f48c8de1d3aa2b511c1faf357ff4fc8316450608..d3f65c3469355431aa0837c7df43ecf59505c072 100644
--- a/Source/core/animation/InertEffect.cpp
+++ b/Source/core/animation/InertEffect.cpp
@@ -58,8 +58,7 @@ void InertEffect::sample(OwnPtr<Vector<RefPtr<Interpolation>>>& result)
 
     double iteration = currentIteration();
     ASSERT(iteration >= 0);
-    // FIXME: Handle iteration values which overflow int.
-    m_model->sample(static_cast<int>(iteration), timeFraction(), iterationDuration(), result);
+    m_model->sample(clampTo<int>(iteration, 0), timeFraction(), iterationDuration(), result);
 }
 
 double InertEffect::calculateTimeToEffectChange(bool, double, double) const