Merge to XFA: Pass v8::Isolate to PDFium at init time.

fpdfsdk/src/javascript/JS_Runtime.cpp

Index: fpdfsdk/src/javascript/JS_Runtime.cpp
diff --git a/fpdfsdk/src/javascript/JS_Runtime.cpp b/fpdfsdk/src/javascript/JS_Runtime.cpp
index f20615402952c1cb44d1c6dc62aa6bb7dfcb98c7..bc5443daf614e609880efcc22ea0dad9b8a1df53 100644
--- a/fpdfsdk/src/javascript/JS_Runtime.cpp
+++ b/fpdfsdk/src/javascript/JS_Runtime.cpp
@@ -45,17 +45,18 @@ CJS_Runtime::CJS_Runtime(CPDFDoc_Environment* pApp)
   if (CPDFXFA_App::GetInstance()->GetJSERuntime()) {
     // TODO(tsepez): CPDFXFA_App should also use the embedder provided isolate.
     m_isolate = (v8::Isolate*)CPDFXFA_App::GetInstance()->GetJSERuntime();
-  } else 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 FXJS_ArrayBufferAllocator());
-
-    v8::Isolate::CreateParams params;
-    params.array_buffer_allocator = m_pArrayBufferAllocator.get();
-    m_isolate = v8::Isolate::New(params);
-    m_isolateManaged = true;
+  } else {
+    IPDF_JSPLATFORM* pPlatform = m_pApp->GetFormFillInfo()->m_pJsPlatform;
+    if (pPlatform->version <= 2) {
+      unsigned int embedderDataSlot = 0;
+      v8::Isolate* pExternalIsolate = nullptr;
+      if (pPlatform->version == 2) {
+        pExternalIsolate = reinterpret_cast<v8::Isolate*>(pPlatform->m_isolate);
+        embedderDataSlot = pPlatform->m_v8EmbedderSlot;
+      }
+      FXJS_Initialize(embedderDataSlot, pExternalIsolate);
+    }
+    m_isolateManaged = FXJS_GetIsolate(&m_isolate);
   }
 
   v8::Isolate* isolate = m_isolate;
@@ -69,10 +70,6 @@ CJS_Runtime::CJS_Runtime(CPDFDoc_Environment* pApp)
     return;
   }
 
-  unsigned int embedderDataSlot = 0;
-  if (m_pApp->GetFormFillInfo()->m_pJsPlatform->version >= 2)
-    embedderDataSlot = pApp->GetFormFillInfo()->m_pJsPlatform->m_v8EmbedderSlot;
-  FXJS_Initialize(embedderDataSlot);
   DefineJSObjects();
   CPDFXFA_App::GetInstance()->SetJavaScriptInitialized(TRUE);