[Athena: Cleanup] consolidate ChromeAppActivity and ShellAppActivity

athena/content/content_activity_factory.cc

Index: athena/content/content_activity_factory.cc
diff --git a/athena/content/content_activity_factory.cc b/athena/content/content_activity_factory.cc
index aaa4e2090151a6db9279e994d43c9407d15244fd..ef00f1c9996ed347442719d1a480a089e86c0b80 100644
--- a/athena/content/content_activity_factory.cc
+++ b/athena/content/content_activity_factory.cc
@@ -4,6 +4,7 @@
 
 #include "athena/content/content_activity_factory.h"
 
+#include "athena/content/app_activity.h"
 #include "athena/content/web_activity.h"
 #include "base/logging.h"
 
@@ -21,6 +22,12 @@ Activity* ContentActivityFactory::CreateWebActivity(
   return new WebActivity(browser_context, title, url);
 }
 
+Activity* ContentActivityFactory::CreateAppActivity(
+    extensions::AppWindow* app_window,
+    views::WebView* web_view) {
+  return new AppActivity(app_window, web_view);
+}
+
 ActivityFactory* CreateContentActivityFactory() {
   return new ContentActivityFactory();
 }