DevTools: pass agent host id to the renderer (Blink).

Source/core/inspector/InspectorResourceAgent.h

Index: Source/core/inspector/InspectorResourceAgent.h
diff --git a/Source/core/inspector/InspectorResourceAgent.h b/Source/core/inspector/InspectorResourceAgent.h
index cd0dca57a2eb55b629a169d70442e13f9bb93104..8eafcc7ad50be912cf02073ac54b358b3f5e93c8 100644
--- a/Source/core/inspector/InspectorResourceAgent.h
+++ b/Source/core/inspector/InspectorResourceAgent.h
@@ -142,6 +142,7 @@ public:
     virtual void loadResourceForFrontend(ErrorString*, const String& frameId, const String& url, const RefPtr<JSONObject>* requestHeaders, PassRefPtr<LoadResourceForFrontendCallback>) OVERRIDE;
 
     // Called from other agents.
+    void setHostId(const String&);
     bool fetchResourceContent(LocalFrame*, const KURL&, String* content, bool* base64Encoded);
 
 private:
@@ -152,6 +153,7 @@ private:
     InspectorPageAgent* m_pageAgent;
     InspectorFrontend::Network* m_frontend;
     String m_userAgentOverride;
+    String m_hostId;
     OwnPtr<NetworkResourcesData> m_resourcesData;
 
     typedef HashMap<ThreadableLoaderClient*, RefPtr<XHRReplayData> > PendingXHRReplayDataMap;