Refactor extension handling code from AppShimHost into ExtensionAppShimHandler.

apps/app_shim/extension_app_shim_handler_mac.h

Index: apps/app_shim/extension_app_shim_handler_mac.h
diff --git a/apps/app_shim/extension_app_shim_handler_mac.h b/apps/app_shim/extension_app_shim_handler_mac.h
new file mode 100644
index 0000000000000000000000000000000000000000..ea9a8c7eeea8eb945dd11429f242b006dd21777b
--- /dev/null
+++ b/apps/app_shim/extension_app_shim_handler_mac.h
@@ -0,0 +1,60 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef APPS_APP_SHIM_EXTENSION_APP_SHIM_HANDLER_H_
+#define APPS_APP_SHIM_EXTENSION_APP_SHIM_HANDLER_H_
+
+#include <map>
+#include <string>
+
+#include "apps/app_shim/app_shim_handler_mac.h"
+#include "content/public/browser/notification_observer.h"
+#include "content/public/browser/notification_registrar.h"
+
+class Profile;
+
+namespace apps {
+
+// This app shim handler that handles events for app shims that correspond to an
+// extension.
+class ExtensionAppShimHandler : public AppShimHandler,
+                                public content::NotificationObserver {
+ public:
+  ExtensionAppShimHandler();
+  virtual ~ExtensionAppShimHandler();
+
+  // AppShimHandler overrides:
+  virtual bool OnShimLaunch(Host* host) OVERRIDE;
+  virtual void OnShimClose(Host* host) OVERRIDE;
+  virtual void OnShimFocus(Host* host) OVERRIDE;
+
+ protected:
+  typedef std::map<std::pair<Profile*, std::string>, AppShimHandler::Host*>
+      HostMap;
+
+  // Exposed for testing.
+  HostMap& hosts() { return hosts_; }
+  content::NotificationRegistrar& registrar() { return registrar_; }
+
+ private:
+  virtual bool LaunchApp(Profile* profile, const std::string& app_id);
+
+  // Listen to the NOTIFICATION_EXTENSION_HOST_DESTROYED message to detect when
+  // an app closes. When that happens, call OnAppClosed on the relevant
+  // AppShimHandler::Host which causes the app shim process to quit.
+  // The host will call OnShimClose on this.
+  virtual void Observe(int type,
+                       const content::NotificationSource& source,
+                       const content::NotificationDetails& details) OVERRIDE;
+
+  void CloseShim(Profile* profile, const std::string& app_id);
+
+  HostMap hosts_;
+
+  content::NotificationRegistrar registrar_;
+};
+
+}  // namespace apps
+
+#endif  // APPS_APP_SHIM_EXTENSION_APP_SHIM_HANDLER_H_