Don't dispose the isolate if its provided by the embedder

fpdfsdk/src/javascript/JS_Runtime.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 "../../include/javascript/JavaScript.h"
 #include "../../include/javascript/IJavaScript.h"
 #include "../../include/javascript/JS_EventHandler.h"
 #include "../../include/javascript/JS_Runtime.h"
@@ skipping 80 matching lines @@
   free(data);
 }
 
 /* ------------------------------ CJS_Runtime ------------------------------ */
 
 CJS_Runtime::CJS_Runtime(CPDFDoc_Environment* pApp)
     : m_pApp(pApp),
       m_pDocument(NULL),
       m_bBlocking(FALSE),
       m_pFieldEventPath(NULL),
-      m_isolate(NULL) {
+      m_isolate(NULL),
+      m_isolateManaged(false) {
   if (m_pApp->GetFormFillInfo()->m_pJsPlatform->version >= 2) {
     m_isolate = reinterpret_cast<v8::Isolate*>(
         m_pApp->GetFormFillInfo()->m_pJsPlatform->m_isolate);
   }
   if (!m_isolate) {
     m_pArrayBufferAllocator.reset(new CJS_ArrayBufferAllocator());
 
     v8::Isolate::CreateParams params;
     params.array_buffer_allocator = m_pArrayBufferAllocator.get();
     m_isolate = v8::Isolate::New(params);
+    m_isolateManaged = true;
   }
 
   InitJSObjects();
 
   CJS_Context* pContext = (CJS_Context*)NewContext();
   JS_InitialRuntime(*this, this, pContext, m_context);
   ReleaseContext(pContext);
 }
 
 CJS_Runtime::~CJS_Runtime() {
   for (int i = 0, sz = m_ContextArray.GetSize(); i < sz; i++)
     delete m_ContextArray.GetAt(i);
 
   m_ContextArray.RemoveAll();
 
   JS_ReleaseRuntime(*this, m_context);
 
   RemoveEventsInLoop(m_pFieldEventPath);
 
   m_pApp = NULL;
   m_pDocument = NULL;
   m_pFieldEventPath = NULL;
   m_context.Reset();
 
-  // m_isolate->Exit();
-  m_isolate->Dispose();
+  if (m_isolateManaged)
+    m_isolate->Dispose();
 }
 
 FX_BOOL CJS_Runtime::InitJSObjects() {
   v8::Isolate::Scope isolate_scope(GetIsolate());
   v8::HandleScope handle_scope(GetIsolate());
   v8::Local<v8::Context> context = v8::Context::New(GetIsolate());
   v8::Context::Scope context_scope(context);
   // 0 - 8
   if (CJS_Border::Init(*this, JS_STATIC) < 0)
     return FALSE;
@@ skipping 177 matching lines @@
 
 v8::Local<v8::Context> CJS_Runtime::NewJSContext() {
   return v8::Local<v8::Context>::New(m_isolate, m_context);
 }
 
 CFX_WideString ChangeObjName(const CFX_WideString& str) {
   CFX_WideString sRet = str;
   sRet.Replace(L"_", L".");
   return sRet;
 }