Add Isolate parameter to Persistent class.

samples/process.cc

Index: samples/process.cc
diff --git a/samples/process.cc b/samples/process.cc
index ae6a5500cd1bb506dde593725189a3b0269315fa..d8d95129b07b8830d47a197dbafaff0434d5a86f 100644
--- a/samples/process.cc
+++ b/samples/process.cc
@@ -273,8 +273,9 @@ JsHttpRequestProcessor::~JsHttpRequestProcessor() {
   // Dispose the persistent handles.  When noone else has any
   // references to the objects stored in the handles they will be
   // automatically reclaimed.
-  context_.Dispose();
-  process_.Dispose();
+  v8::Isolate* isolate = context_->GetIsolate();
+  context_.Dispose(isolate);
+  process_.Dispose(isolate);
 }