Merge IFWL_App and FWL_AppImp together

xfa/fxfa/app/xfa_ffapp.cpp

 // Copyright 2014 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.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "xfa/fxfa/xfa_ffapp.h"
 
 #include <algorithm>
 #include <utility>
@@ skipping 56 matching lines @@
   return FALSE;
 }
 
 void CXFA_FileRead::Release() {
   delete this;
 }
 
 CXFA_FFApp::CXFA_FFApp(IXFA_AppProvider* pProvider)
     : m_pProvider(pProvider),
       m_pWidgetMgrDelegate(nullptr),
-      m_pFWLApp(IFWL_App::Create(this)) {
+      m_pFWLApp(pdfium::MakeUnique<IFWL_App>(this)) {
   FWL_SetApp(m_pFWLApp.get());
-  m_pFWLApp->Initialize();
   CXFA_TimeZoneProvider::Create();
 }
 
 CXFA_FFApp::~CXFA_FFApp() {
-  if (m_pFWLApp) {
-    m_pFWLApp->Finalize();
-    m_pFWLApp->Release();
-  }
-
   CXFA_TimeZoneProvider::Destroy();
 }
 
 CXFA_FFDocHandler* CXFA_FFApp::GetDocHandler() {
   if (!m_pDocHandler)
     m_pDocHandler.reset(new CXFA_FFDocHandler);
   return m_pDocHandler.get();
 }
 
 CXFA_FFDoc* CXFA_FFApp::CreateDoc(IXFA_DocEnvironment* pDocEnvironment,
@@ skipping 49 matching lines @@
     pDelegate->OnSetCapability(FWL_WGTMGR_DisableThread |
                                FWL_WGTMGR_DisableForm);
     m_pWidgetMgrDelegate = pDelegate;
   }
   return m_pAdapterWidgetMgr.get();
 }
 
 IFWL_AdapterTimerMgr* CXFA_FFApp::GetTimerMgr() const {
   return m_pProvider->GetTimerMgr();
 }