GitLab

- Add KioskAppManager::RetryFailedAppDataFetch that starts fetch for failed
  app data fetch (status == STATUS_ERROR);
- RetryFailedAppDataFetch when kiosk app is added/removed (include policy refrech);
- RetryFailedAppDataFetch on login screen when portal detection is passed;
- Add max auto retry times for underlying URLFetcher's 5xx retry and
  ERR_NETWORK_CHANGED retry in WebstoreDataFetcher;
- KioskAppData sets max retry times to 3 for its webstore data fetch;

BUG=392670

Review URL: https://codereview.chromium.org/386633003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@282577 0039d316-1c4b-4281-b951-d872f2087c98