AppModelBuilder to athena.

athena/activity/public/activity_factory.h

Index: athena/activity/public/activity_factory.h
diff --git a/athena/activity/public/activity_factory.h b/athena/activity/public/activity_factory.h
index 8cea669e10ca76f0619cc54f9551c48382187185..c617eee774310f5aa8e6257a8ad1c0aeeac607ee 100644
--- a/athena/activity/public/activity_factory.h
+++ b/athena/activity/public/activity_factory.h
@@ -31,6 +31,10 @@ class ATHENA_EXPORT ActivityFactory {
   // Create an activity of a web page.
   virtual Activity* CreateWebActivity(content::BrowserContext* browser_context,
                                       const GURL& url) = 0;
+
+  // Create an activity of an app.
+  virtual Activity* CreateAppActivity(content::BrowserContext* browser_context,
+                                      const std::string& app_id) = 0;
 };
 
 }  // namespace athena