Remove IWFL_WidgetMgr in favor of CFWL_WidgetMgr

xfa/fwl/core/fwl_appimp.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/fwl/core/fwl_appimp.h"
 
 #include "xfa/fwl/core/fwl_noteimp.h"
 #include "xfa/fwl/core/fwl_widgetmgrimp.h"
@@ skipping 58 matching lines @@
   return FWL_Error::Succeeded;
 }
 FWL_Error CFWL_AppImp::Finalize() {
   m_pWidgetMgr.reset();
   return FWL_Error::Succeeded;
 }
 CXFA_FFApp* CFWL_AppImp::GetAdapterNative() const {
   return m_pAdapterNative;
 }
 CXFA_FWLAdapterWidgetMgr* FWL_GetAdapterWidgetMgr() {
-  return static_cast<CFWL_WidgetMgr*>(FWL_GetWidgetMgr())
+  return static_cast<CFWL_WidgetMgr*>(IFWL_WidgetMgr::GetInstance())
       ->GetAdapterWidgetMgr();
 }
 IFWL_WidgetMgr* CFWL_AppImp::GetWidgetMgr() const {
   return m_pWidgetMgr.get();
 }
 
 void CFWL_AppImp::SetThemeProvider(IFWL_ThemeProvider* pThemeProvider) {
   m_pThemeProvider = pThemeProvider;
 }
 
@@ skipping 15 matching lines @@
 }
 
 static IFWL_App* g_theApp = nullptr;
 IFWL_App* FWL_GetApp() {
   return g_theApp;
 }
 
 void FWL_SetApp(IFWL_App* pApp) {
   g_theApp = pApp;
 }