arc: Fix race conditon when Play Store is started too early.

chrome/browser/ui/app_list/arc/arc_app_launcher.h

 // Copyright 2016 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_ARC_ARC_APP_LAUNCHER_H_
 #define CHROME_BROWSER_UI_APP_LIST_ARC_ARC_APP_LAUNCHER_H_
 
 #include <string>
 
 #include "base/macros.h"
 #include "chrome/browser/ui/app_list/arc/arc_app_list_prefs.h"
 
 namespace content {
 class BrowserContext;
 }
 
 // Helper class for deferred ARC app launching in case app is not ready on the
 // moment of request.
 class ArcAppLauncher : public ArcAppListPrefs::Observer {
  public:
   ArcAppLauncher(content::BrowserContext* context,
                  const std::string& app_id,
-                 bool landscape_layout);
+                 bool landscape_layout,
+                 bool deferred_launch_allowed);
   ~ArcAppLauncher() override;
 
   bool app_launched() const { return app_launched_; }
 
   // ArcAppListPrefs::Observer:
   void OnAppRegistered(const std::string& app_id,
                        const ArcAppListPrefs::AppInfo& app_info) override;
   void OnAppReadyChanged(const std::string& app_id, bool ready) override;
 
  private:
   void LaunchApp();
 
   // Unowned pointer.
   content::BrowserContext* context_;
   // ARC app id and requested layout.
   const std::string app_id_;
   const bool landscape_layout_;
-  // Flag idicating that ARC app was launched.
+  // If it is set to true that means app is allowed to launch in deferred mode
+  // once it is registered, regardless it is ready or not. Otherwise app is
+  // launched when it becomes ready.
+  const bool deferred_launch_allowed_;
+  // Flag indicating that ARC app was launched.
   bool app_launched_ = false;
 
   DISALLOW_COPY_AND_ASSIGN(ArcAppLauncher);
 };
 
 #endif  // CHROME_BROWSER_UI_APP_LIST_ARC_ARC_APP_LAUNCHER_H_