Notify launcher page with onTransitionChanged event

chrome/browser/ui/app_list/launcher_page_event_dispatcher.h

+// Copyright 2014 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 CHROME_BROWSER_UI_APP_LIST_LAUNCHER_PAGE_EVENT_DISPATCHER_H_
+#define CHROME_BROWSER_UI_APP_LIST_LAUNCHER_PAGE_EVENT_DISPATCHER_H_
+
+#include <string>
+
+#include "base/macros.h"
+#include "base/memory/scoped_ptr.h"
+
+class Profile;
+
+namespace base {
+class ListValue;
+}
+
+namespace app_list {
+
+// A class which sends API events to the custom launcher page.
+class LauncherPageEventDispatcher {
+ public:
+  LauncherPageEventDispatcher(Profile* profile,
+                              const std::string& extension_id);
+  ~LauncherPageEventDispatcher();
+
+  void ProgressChanged(double progress);
+
+ private:
+  void SendEventToLauncherPage(const std::string& event_name,
+                               scoped_ptr<base::ListValue> args);
+
+  Profile* profile_;
+  std::string extension_id_;
+
+  DISALLOW_COPY_AND_ASSIGN(LauncherPageEventDispatcher);
+};
+
+}  // namespace app_list
+
+#endif  // CHROME_BROWSER_UI_APP_LIST_LAUNCHER_PAGE_EVENT_DISPATCHER_H_