Migrate WTF::Vector::append() to ::push_back() [part 3 of N]

third_party/WebKit/Source/core/css/cssom/CSSVariableReferenceValueTest.cpp

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "core/css/cssom/CSSStyleVariableReferenceValue.h"
 
 #include "core/css/cssom/CSSUnparsedValue.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace blink {
 
 TEST(CSSVariableReferenceValueTest, EmptyList) {
   HeapVector<StringOrCSSVariableReferenceValue> fragments;
   CSSUnparsedValue* unparsedValue = CSSUnparsedValue::create(fragments);
 
   CSSStyleVariableReferenceValue* variableReferenceValue =
       CSSStyleVariableReferenceValue::create("test", unparsedValue);
 
   EXPECT_EQ(variableReferenceValue->variable(), "test");
   EXPECT_EQ(variableReferenceValue->fallback(), unparsedValue);
 }
 
 TEST(CSSVariableReferenceValueTest, MixedList) {
   HeapVector<StringOrCSSVariableReferenceValue> fragments;
-  fragments.append(StringOrCSSVariableReferenceValue::fromString("string"));
-  fragments.append(
+  fragments.push_back(StringOrCSSVariableReferenceValue::fromString("string"));
+  fragments.push_back(
       StringOrCSSVariableReferenceValue::fromCSSVariableReferenceValue(
           CSSStyleVariableReferenceValue::create(
               "Variable", CSSUnparsedValue::fromString("Fallback"))));
-  fragments.append(StringOrCSSVariableReferenceValue());
+  fragments.push_back(StringOrCSSVariableReferenceValue());
 
   CSSUnparsedValue* unparsedValue = CSSUnparsedValue::create(fragments);
 
   CSSStyleVariableReferenceValue* variableReferenceValue =
       CSSStyleVariableReferenceValue::create("test", unparsedValue);
 
   EXPECT_EQ(variableReferenceValue->variable(), "test");
   EXPECT_EQ(variableReferenceValue->fallback(), unparsedValue);
 }
 
 }  // namespace blink