Prevent A/B test enrollment hook from firing for unsampled

Bug: T297662
Change-Id: Ibeca32a3c0fab7de403d69ea274c653cf4bd6c0e
(cherry picked from commit 60553ff324)

resources/skins.vector.es6/AB.js

@@ -2,7 +2,7 @@
  * Example A/B test configuration for sticky header:
  *
  * $wgVectorABTestEnrollment = [
- *     'name' => 'vector.sticky_header_2021_11',
+ *     'name' => 'vector.sticky_header',
  *     'enabled' => true,
  *     'buckets' => [
  *         'unsampled' => [
@@ -101,7 +101,7 @@ function isInTestGroup( bucket, targetGroup ) {
 function initAB( bucket ) {
 	// Send data to WikimediaEvents to log A/B test initialization if experiment is enabled
 	// and if the user is logged in.
-	if ( ABTestConfig.enabled && !mw.user.isAnon() ) {
+	if ( ABTestConfig.enabled && !mw.user.isAnon() && bucket !== 'unsampled' ) {
 		// @ts-ignore
 		mw.hook( 'mediawiki.web_AB_test_enrollment' ).fire( getABTestGroupExperimentName() );
 

resources/skins.vector.es6/stickyHeader.js

@@ -12,7 +12,7 @@ const
 	USER_MENU_ID = 'p-personal',
 	VECTOR_USER_LINKS_SELECTOR = '.vector-user-links',
 	SEARCH_TOGGLE_SELECTOR = '.vector-sticky-header-search-toggle',
-	STICKY_HEADER_EXPERIMENT_NAME = 'vector.sticky_header_2021_11';
+	STICKY_HEADER_EXPERIMENT_NAME = 'vector.sticky_header';
 
 /**
  * Copies attribute from an element to another.

skin.json

@@ -378,7 +378,7 @@
 		},
 		"VectorWebABTestEnrollment": {
 			"value": {
-				"name": "vector.sticky_header_2021_11",
+				"name": "vector.sticky_header",
 				"enabled": false,
 				"buckets": {
 					"unsampled": {