1. Add successorTabId to the Tab type, so that it will be returned in, e.g.,
browser.tabs.get calls
2. Extend or create the following methods on the browser.tabs API:
- update: add successorTabId as an optional property on the provided
updateProperties object
- moveInSuccession: new method that manipulates tab successors in bulk
Differential Revision: https://phabricator.services.mozilla.com/D9272