bindings: Pass is_null flag to attribute setters when they are nullable

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

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 588 matching lines @@
     KeyframeEffect* transition = KeyframeEffect::Create(
         element, model, inert_animation->SpecifiedTiming(),
         KeyframeEffectReadOnly::kTransitionPriority, event_delegate);
     Animation* animation = element->GetDocument().Timeline().Play(transition);
     if (property.IsCSSCustomProperty()) {
       animation->setId(property.CustomPropertyName());
     } else {
       animation->setId(getPropertyName(property.CssProperty()));
     }
     // Set the current time as the start time for retargeted transitions
-    if (retargeted_compositor_transitions.Contains(property))
-      animation->setStartTime(element->GetDocument().Timeline().currentTime());
+    if (retargeted_compositor_transitions.Contains(property)) {
+      animation->setStartTime(element->GetDocument().Timeline().currentTime(),
+                              false);
+    }
     animation->Update(kTimingUpdateOnDemand);
     running_transition.animation = animation;
     transitions_.Set(property, running_transition);
     DCHECK(isValidCSSPropertyID(property.CssProperty()));
     UseCounter::CountAnimatedCSS(element->GetDocument(),
                                  property.CssProperty());
 
     // TODO(crbug.com/458925): Remove legacy histogram and counts
     DEFINE_STATIC_LOCAL(SparseHistogram, property_histogram,
                         ("WebCore.Animation.CSSProperties"));
@@ skipping 607 matching lines @@
              IsCustomPropertyHandle);
 }
 
 DEFINE_TRACE(CSSAnimations) {
   visitor->Trace(transitions_);
   visitor->Trace(pending_update_);
   visitor->Trace(running_animations_);
 }
 
 }  // namespace blink