Re-land "Preserve m_pDynamicObjsMap until FXJS_PerIsolateData is destroyed.""

fpdfsdk/include/jsapi/fxjs_v8.h

 // 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
 
 // FXJS_V8 is a layer that makes it easier to define native objects in V8, but
 // has no knowledge of PDF-specific native objects. It could in theory be used
 // to implement other sets of native objects.
 
@@ skipping 79 matching lines @@
 
  private:
   MapType m_map;
 };
 
 class FXJS_PerIsolateData {
  public:
   static void SetUp(v8::Isolate* pIsolate);
   static FXJS_PerIsolateData* Get(v8::Isolate* pIsolate);
   void CreateDynamicObjsMap(v8::Isolate* pIsolate) {
-    m_pDynamicObjsMap = new V8TemplateMap(pIsolate);
+    if (!m_pDynamicObjsMap)
+      m_pDynamicObjsMap = new V8TemplateMap(pIsolate);
   }
   void ReleaseDynamicObjsMap() {
     delete m_pDynamicObjsMap;
     m_pDynamicObjsMap = nullptr;
   }
 
   std::vector<CFXJS_ObjDefinition*> m_ObjectDefnArray;
 #ifdef PDF_ENABLE_XFA
   CFXJSE_RuntimeData* m_pFXJSERuntimeData;
 #endif  // PDF_ENABLE_XFA
@@ skipping 184 matching lines @@
 double FXJS_ToNumber(v8::Isolate* pIsolate, v8::Local<v8::Value> pValue);
 v8::Local<v8::Object> FXJS_ToObject(v8::Isolate* pIsolate,
                                     v8::Local<v8::Value> pValue);
 CFX_WideString FXJS_ToString(v8::Isolate* pIsolate,
                              v8::Local<v8::Value> pValue);
 v8::Local<v8::Array> FXJS_ToArray(v8::Isolate* pIsolate,
                                   v8::Local<v8::Value> pValue);
 void FXJS_ValueCopy(v8::Local<v8::Value>& pTo, v8::Local<v8::Value> pFrom);
 
 #endif  // FPDFSDK_INCLUDE_JSAPI_FXJS_V8_H_