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

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

Index: third_party/WebKit/Source/core/animation/EffectStackTest.cpp
diff --git a/third_party/WebKit/Source/core/animation/EffectStackTest.cpp b/third_party/WebKit/Source/core/animation/EffectStackTest.cpp
index 8273145cab9b043d0519b00255b692737aac135f..13cea9f0f556abb14a8af9cf7b3d8fcd4fcd551c 100644
--- a/third_party/WebKit/Source/core/animation/EffectStackTest.cpp
+++ b/third_party/WebKit/Source/core/animation/EffectStackTest.cpp
@@ -116,8 +116,8 @@ TEST_F(AnimationEffectStackTest, NewAnimations) {
       makeEffectModel(CSSPropertyFontSize, AnimatableDouble::create(3)));
   InertEffect* inert2 = makeInertEffect(
       makeEffectModel(CSSPropertyZIndex, AnimatableDouble::create(4)));
-  newAnimations.append(inert1);
-  newAnimations.append(inert2);
+  newAnimations.push_back(inert1);
+  newAnimations.push_back(inert2);
   ActiveInterpolationsMap result = EffectStack::activeInterpolations(
       &element->elementAnimations()->effectStack(), &newAnimations, 0,
       KeyframeEffectReadOnly::DefaultPriority);