Cleanup env variable names

fpdfsdk/formfiller/cffl_checkbox.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 "fpdfsdk/formfiller/cffl_checkbox.h"
 
 #include "fpdfsdk/cpdfsdk_formfillenvironment.h"
 #include "fpdfsdk/cpdfsdk_widget.h"
@@ skipping 31 matching lines @@
                               uint32_t nFlags) {
   switch (nChar) {
     case FWL_VKEY_Return:
     case FWL_VKEY_Space: {
       CPDFSDK_PageView* pPageView = pAnnot->GetPageView();
       ASSERT(pPageView);
 
       FX_BOOL bReset = FALSE;
       FX_BOOL bExit = FALSE;
       CPDFSDK_Annot::ObservedPtr pObserved(m_pWidget);
-      m_pEnv->GetInteractiveFormFiller()->OnButtonUp(&pObserved, pPageView,
-                                                     bReset, bExit, nFlags);
+      m_pFormFillEnv->GetInteractiveFormFiller()->OnButtonUp(
+          &pObserved, pPageView, bReset, bExit, nFlags);
       if (!pObserved) {
         m_pWidget = nullptr;
         return TRUE;
       }
       if (bReset || bExit)
         return TRUE;
 
       CFFL_FormFiller::OnChar(pAnnot, nChar, nFlags);
       if (CPWL_CheckBox* pWnd = (CPWL_CheckBox*)GetPDFWindow(pPageView, TRUE))
         pWnd->SetCheck(!pWnd->IsChecked());
@@ skipping 43 matching lines @@
           }
         }
       }
     }
 
     m_pWidget->SetCheck(bNewChecked, false);
     m_pWidget->UpdateField();
     SetChangeMark();
   }
 }