Gerrit issues, including issue history, have been migrated into the new Gerrit Code Review Tracker.
New issues can be filed at https://issues.gerritcodereview.com/issues/new
You can learn more about the new issue tracker's features at: developers.google.com/issue-tracker
The Monorail issues are read-only now. Accessing a Monorail issue automatically redirects to the issue in the new tracker. You can still access the issues in Monorail by appending “&no_tracker_redirect” to the URL (e.g. https://bugs.chromium.org/p/gerrit/issues/detail?id=15057&no_tracker_redirect).
Also see this announcement.