[inspector] Create InjectedScript per session in each context

test/inspector/isolate-data.h

Index: test/inspector/isolate-data.h
diff --git a/test/inspector/isolate-data.h b/test/inspector/isolate-data.h
index f12a6501a33ca7066a743e28d0e739ece6021f36..a94316ff9bedbbf0b2bc26a04804e35b380b09ab 100644
--- a/test/inspector/isolate-data.h
+++ b/test/inspector/isolate-data.h
@@ -58,6 +58,7 @@ class IsolateData : public v8_inspector::V8InspectorClient {
                           bool recurring);
   void AsyncTaskStarted(void* task);
   void AsyncTaskFinished(void* task);
+  void AddInspectedObject(int session_id, v8::Local<v8::Value> object);
 
   // Test utilities.
   void SetCurrentTimeMS(double time);