Implement kiosk multiple apps feature.

chrome/browser/chromeos/app_mode/startup_app_launcher.h

Index: chrome/browser/chromeos/app_mode/startup_app_launcher.h
diff --git a/chrome/browser/chromeos/app_mode/startup_app_launcher.h b/chrome/browser/chromeos/app_mode/startup_app_launcher.h
index 4133b4a65f4f516e89f7ca0d7637876bbcdad407..4f8a1de755da1fcb2d874bf9d68479cd4875343d 100644
--- a/chrome/browser/chromeos/app_mode/startup_app_launcher.h
+++ b/chrome/browser/chromeos/app_mode/startup_app_launcher.h
@@ -91,6 +91,7 @@ class StartupAppLauncher : public base::SupportsWeakPtr<StartupAppLauncher>,
 
   void InitializeTokenService();
   void MaybeInitializeNetwork();
+  void MaybeInstallSecondaryApps();
   void MaybeLaunchApp();
 
   void StartLoadingOAuthFile();
@@ -99,6 +100,17 @@ class StartupAppLauncher : public base::SupportsWeakPtr<StartupAppLauncher>,
 
   void OnKioskAppDataLoadStatusChanged(const std::string& app_id);
 
+  // Returns true if any secondary app is pending.
+  bool IsAnySecondaryAppPending() const;
+
+  // Returns true if all secondary apps have been installed.
+  bool AreSecondaryAppsInstalled() const;
+
+  // Returns true if secondary apps are declared in manifest.
+  bool HasSecondaryApps() const;
+
+  const extensions::Extension* GetPrimaryAppExtension() const;
+
   // OAuth2TokenService::Observer overrides.
   void OnRefreshTokenAvailable(const std::string& account_id) override;
   void OnRefreshTokensLoaded() override;