Add ptr_util.h from base until std::make_unique<> available

testing/js_embedder_test.cpp

 // Copyright 2015 PDFium 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 "testing/js_embedder_test.h"
+#include "third_party/base/ptr_util.h"
 
 JSEmbedderTest::JSEmbedderTest()
     : m_pArrayBufferAllocator(new FXJS_ArrayBufferAllocator),
       m_pIsolate(nullptr) {}
 
 JSEmbedderTest::~JSEmbedderTest() {}
 
 void JSEmbedderTest::SetUp() {
   v8::Isolate::CreateParams params;
   params.array_buffer_allocator = m_pArrayBufferAllocator.get();
   m_pIsolate = v8::Isolate::New(params);
 
   EmbedderTest::SetExternalIsolate(m_pIsolate);
   EmbedderTest::SetUp();
 
   v8::Isolate::Scope isolate_scope(m_pIsolate);
   v8::HandleScope handle_scope(m_pIsolate);
   FXJS_PerIsolateData::SetUp(m_pIsolate);
-  m_Engine = WrapUnique(new CFXJS_Engine(m_pIsolate));
+  m_Engine = pdfium::MakeUnique<CFXJS_Engine>(m_pIsolate);
   m_Engine->InitializeEngine();
 }
 
 void JSEmbedderTest::TearDown() {
   m_Engine->ReleaseEngine();
   m_Engine.reset();
   EmbedderTest::TearDown();
   m_pIsolate->Dispose();
   m_pIsolate = nullptr;
 }
 
 v8::Isolate* JSEmbedderTest::isolate() {
   return m_pIsolate;
 }
 
 v8::Local<v8::Context> JSEmbedderTest::GetV8Context() {
   return m_Engine->GetPersistentContext();
 }