VideoPress: Introduce private videos (#22948)

Adds settings for controlling VideoPress video privacy. The settings work at two levels of granularity

* Site level: This is set from Jetpack Settings. When it's on, all video views are restricted to site members by default.
* Video Level: An individual video's privacy setting can be changed from the block.

The possible values are:

* Public (this specific video can be viewed by anyone).
* Private (this specific video can be viewed by site members).
* Site default (default for new videos, the video privacy setting follows the site-level setting).

Co-authored-by: John Caruso <johncaruso@gmail.com>
Co-authored-by: Dan Roundhill <dan@automattic.com>
Co-authored-by: thedebian <thedebian@users.noreply.github.com>

Committed via a GitHub action: https://github.com/Automattic/jetpack/actions/runs/2109066003

CHANGELOG.md

@@ -9,6 +9,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 This is an alpha version! The changes listed here are not final.
 
+### Added
+- Adding new site option to be synced.
+
 ## [1.30.6] - 2022-04-06
 ### Changed
 - Updated package dependencies.

src/class-defaults.php

@@ -172,6 +172,7 @@ class Defaults {
 		'wpcom_is_fse_activated',
 		'wpcom_publish_comments_with_markdown',
 		'wpcom_publish_posts_with_markdown',
+		'videopress_private_enabled_for_site',
 	);
 
 	/**