Clean up singleton implementation

fpdfsdk/javascript/JS_GlobalData.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/javascript/JS_GlobalData.h"
 
 #include "core/fdrm/crypto/include/fx_crypt.h"
 #include "third_party/base/stl_util.h"
@@ skipping 82 matching lines @@
     0x0e, 0xd0, 0x6b, 0xbb, 0xd5, 0x75, 0x55, 0x8b, 0x6e, 0x6b, 0x19, 0xa0,
     0xf8, 0x77, 0xd5, 0xa3};
 
 // Returns true if non-empty, setting sPropName
 static bool TrimPropName(CFX_ByteString* sPropName) {
   sPropName->TrimLeft();
   sPropName->TrimRight();
   return sPropName->GetLength() != 0;
 }
 
-CJS_GlobalData* CJS_GlobalData::g_Instance = nullptr;
+CJS_GlobalData* CJS_GlobalData::m_pInstance = nullptr;
 
 // static
 CJS_GlobalData* CJS_GlobalData::GetRetainedInstance(CPDFDoc_Environment* pApp) {
-  if (!g_Instance) {
-    g_Instance = new CJS_GlobalData();
+  if (!m_pInstance) {
+    m_pInstance = new CJS_GlobalData();
   }
-  ++g_Instance->m_RefCount;
-  return g_Instance;
+  ++m_pInstance->m_RefCount;
+  return m_pInstance;
 }
 
 void CJS_GlobalData::Release() {
   if (!--m_RefCount) {
-    delete g_Instance;
-    g_Instance = nullptr;
+    delete m_pInstance;
+    m_pInstance = nullptr;
   }
 }
 
 CJS_GlobalData::CJS_GlobalData()
     : m_RefCount(0), m_sFilePath(SDK_JS_GLOBALDATA_FILENAME) {
   LoadGlobalPersistentVariables();
 }
 
 CJS_GlobalData::~CJS_GlobalData() {
   SaveGlobalPersisitentVariables();
@@ skipping 322 matching lines @@
       sData.AppendBlock(&wType, sizeof(uint32_t));
     } break;
     default:
       break;
   }
 }
 
 CJS_KeyValue::CJS_KeyValue() {}
 
 CJS_KeyValue::~CJS_KeyValue() {}