XFA: Pass IFXJS_Runtime via V8 contexts, not V8 isolates

fpdfsdk/src/jsapi/fxjs_v8.cpp

Index: fpdfsdk/src/jsapi/fxjs_v8.cpp
diff --git a/fpdfsdk/src/jsapi/fxjs_v8.cpp b/fpdfsdk/src/jsapi/fxjs_v8.cpp
index 1c9bb878834dabcf9743e6254cc842c7b9911669..d7868f15862c5a83cd42d86f633b247328e0e7f2 100644
--- a/fpdfsdk/src/jsapi/fxjs_v8.cpp
+++ b/fpdfsdk/src/jsapi/fxjs_v8.cpp
@@ -269,8 +269,8 @@ void FXJS_InitializeRuntime(v8::Isolate* pIsolate,
   v8::Context::Scope context_scope(v8Context);
 
   FXJS_PerIsolateData::SetUp(pIsolate);
-  FXJS_PerIsolateData* pData = FXJS_PerIsolateData::Get(pIsolate);
-  pData->m_pFXJSRuntime = pFXRuntime;
+  v8::Local<v8::External> ptr = v8::External::New(pIsolate, pFXRuntime);
+  v8Context->SetEmbedderData(1, ptr);

[jochen (gone - plz use gerrit), 2015/09/25 11:17:10]

we should use kPerContextDataStartIndex + kEmbedderPDFium which is == 3

[Tom Sepez, 2015/09/25 16:40:11]

Ok, I'll make a new constant, but I don't want to force the standalone version
to depend on gin/ (though someday reimplementing this in gin might be sane). 
Again, I'd do this on master first, then move over to  XFA.

 
   int maxID = CFXJS_ObjDefinition::MaxID(pIsolate);
   for (int i = 0; i < maxID; ++i) {