Add P2 organization identifier to site SAL (#18007)

* Add P2 organization identifier to site SAL

Summary: Fixes 1542-gh-p2 by adding P2 `organization_id` to sites' details.

Test Plan:
Sites' info should contain P2 organization_id if requested

```
## cURL
curl "https://[private link].2/me/sites?http_envelope=1&site_visibility=all&include_domain_only=true&site_activity=active&fields=ID,name,organization_id" \
     -H 'Authority: [private link]' \
     -H 'Accept: */*'
```

Reviewers: aerych, #lighthouse_team, migueluy

Reviewed By: #lighthouse_team, migueluy

Subscribers: migueluy

Tags: #touches_jetpack_files

Differential Revision: D53881-code

This commit syncs r217904-wpcom.

* SAL: Add P2 organization identifier (#18011)

* SAL: One more PHPCS update (#18018)

Co-authored-by: Brandon Kraft <[email protected]>

json-endpoints/class.wpcom-json-api-get-site-endpoint.php

@@ -49,6 +49,7 @@ class WPCOM_JSON_API_GET_Site_Endpoint extends WPCOM_JSON_API_Endpoint {
 		'single_user_site'            => '(bool) Whether the site is single user. Only returned for WP.com sites and for Jetpack sites with version 3.4 or higher.',
 		'is_vip'                      => '(bool) If the site is a VIP site or not.',
 		'is_following'                => '(bool) If the current user is subscribed to this site in the reader',
+		'organization_id'             => '(int) P2 Organization identifier.',
 		'options'                     => '(array) An array of options/settings for the blog. Only viewable by users with post editing rights to the site. Note: Post formats is deprecated, please see /sites/$id/post-formats/',
 		'plan'                        => '(array) Details of the current plan for this site.',
 		'updates'                     => '(array) An array of available updates for plugins, themes, wordpress, and languages.',
@@ -393,6 +394,11 @@ protected function render_response_key( $key, &$response, $is_user_logged_in ) {
 			case 'is_multisite' :
 				$response[ $key ] = $this->site->is_multisite();
 				break;
+
+			case 'organization_id':
+				$response[ $key ] = $this->site->get_p2_organization_id();
+				break;
+
 			case 'capabilities' :
 				$response[ $key ] = $this->site->get_capabilities();
 				break;

sal/class.json-api-site-base.php

@@ -149,6 +149,15 @@ public function is_automated_transfer() {
 
 	abstract protected function is_wpforteams_site();
 
+	/**
+	 * Getter for the p2 organization ID.
+	 *
+	 * @return int
+	 */
+	public function get_p2_organization_id() {
+		return 0; // WPForTeams\Constants\NO_ORG_ID not loaded.
+	}
+
 	public function is_wpcom_atomic() {
 		return false;
 	}