Feature description:

Some browsers offer the capability to automatically trigger video fullscreen in landscape, sometimes at the browser level and sometimes through a developer opt-in. We want this feature to work just as it does per browser (either automatically or via opt-in).

Related issues:

• amp-ima-video: add builtin support for enter/exit Fullscreen #10597

Related PRs:

• ✨Implement rotate-to-fullscreen #14655
• 🐛Assert only when rotate to fullscreen is enabled #14771
• ✅ Allow <amp-wistia-player rotate-to-fullscreen> #15288
• ✨Disable auto-fullscreen for iframe players in iOS #15061
• ✨ Add firstPlay event #15074 for ABE example
• Add rotate to fullscreen example amp-by-example#1245
• Update <amp-video rotate-to-fullscreen> examples amp-by-example#1267
• ♻️✅ Simplify rotate-to-fullscreen/integration test combo #15480