Migrate WTF::Vector::append() to ::push_back() [part 2 of N]

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

Index: third_party/WebKit/Source/core/animation/AnimationTimeline.cpp
diff --git a/third_party/WebKit/Source/core/animation/AnimationTimeline.cpp b/third_party/WebKit/Source/core/animation/AnimationTimeline.cpp
index 4ee74abdaab110a015a84118cd81e8a346c053f5..8f8659d72da2e114e8f4f972fea9f8b709ba41fd 100644
--- a/third_party/WebKit/Source/core/animation/AnimationTimeline.cpp
+++ b/third_party/WebKit/Source/core/animation/AnimationTimeline.cpp
@@ -110,7 +110,7 @@ HeapVector<Member<Animation>> AnimationTimeline::getAnimations() {
   for (const auto& animation : m_animations) {
     if (animation->effect() &&
         (animation->effect()->isCurrent() || animation->effect()->isInEffect()))
-      animations.append(animation);
+      animations.push_back(animation);
   }
   std::sort(animations.begin(), animations.end(), compareAnimations);
   return animations;
@@ -128,7 +128,7 @@ void AnimationTimeline::serviceAnimations(TimingUpdateReason reason) {
   HeapVector<Member<Animation>> animations;
   animations.reserveInitialCapacity(m_animationsNeedingUpdate.size());
   for (Animation* animation : m_animationsNeedingUpdate)
-    animations.append(animation);
+    animations.push_back(animation);
 
   std::sort(animations.begin(), animations.end(), Animation::hasLowerPriority);