64643 Remove some obsolete return by refs

[nirav7707]

Core ticket: https://core.trac.wordpress.org/ticket/64643

[github-actions]

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[westonruter]

Take it or leave it, but Gemini CLI found some additional possibilities:

diff --git a/src/wp-admin/includes/class-wp-upgrader-skin.php b/src/wp-admin/includes/class-wp-upgrader-skin.php
index 831da3aeba..4c1615cdd2 100644
--- a/src/wp-admin/includes/class-wp-upgrader-skin.php
+++ b/src/wp-admin/includes/class-wp-upgrader-skin.php
@@ -83,9 +83,9 @@ class WP_Upgrader_Skin {
 	 *
 	 * @param WP_Upgrader $upgrader
 	 */
-	public function set_upgrader( &$upgrader ) {
+	public function set_upgrader( $upgrader ) {
 		if ( is_object( $upgrader ) ) {
-			$this->upgrader =& $upgrader;
+			$this->upgrader = $upgrader;
 		}
 		$this->add_strings();
 	}
diff --git a/src/wp-includes/class-wp-hook.php b/src/wp-includes/class-wp-hook.php
index cd6860c0f8..cf6f5aeaca 100644
--- a/src/wp-includes/class-wp-hook.php
+++ b/src/wp-includes/class-wp-hook.php
@@ -375,9 +375,9 @@ final class WP_Hook implements Iterator, ArrayAccess {
 	 *
 	 * @since 4.7.0
 	 *
-	 * @param array $args Arguments to pass to the hook callbacks. Passed by reference.
+	 * @param array $args Arguments to pass to the hook callbacks.
 	 */
-	public function do_all_hook( &$args ) {
+	public function do_all_hook( $args ) {
 		$nesting_level                      = $this->nesting_level++;
 		$this->iterations[ $nesting_level ] = $this->priorities;
 
diff --git a/src/wp-includes/deprecated.php b/src/wp-includes/deprecated.php
index 390d632492..897b1a48a3 100644
--- a/src/wp-includes/deprecated.php
+++ b/src/wp-includes/deprecated.php
@@ -3111,7 +3111,7 @@ function get_theme_data( $theme_file ) {
  *
  * @param array $pages list of page objects
  */
-function update_page_cache( &$pages ) {
+function update_page_cache( $pages ) {
 	_deprecated_function( __FUNCTION__, '3.4.0', 'update_post_cache()' );
 
 	update_post_cache( $pages );
@@ -3177,9 +3177,9 @@ function sticky_class( $post_id = null ) {
  * @deprecated 3.5.0 Use get_post_ancestors()
  * @see get_post_ancestors()
  *
- * @param WP_Post $post Post object, passed by reference (unused).
+ * @param WP_Post $post Post object (unused).
  */
-function _get_post_ancestors( &$post ) {
+function _get_post_ancestors( $post ) {
 	_deprecated_function( __FUNCTION__, '3.5.0' );
 }
 
diff --git a/src/wp-includes/nav-menu-template.php b/src/wp-includes/nav-menu-template.php
index d90fdfa806..29d8a03944 100644
--- a/src/wp-includes/nav-menu-template.php
+++ b/src/wp-includes/nav-menu-template.php
@@ -324,7 +324,7 @@ function wp_nav_menu( $args = array() ) {
  *
  * @param array $menu_items The current menu item objects to which to add the class property information.
  */
-function _wp_menu_item_classes_by_context( &$menu_items ) {
+function _wp_menu_item_classes_by_context( $menu_items ) {
 	global $wp_query, $wp_rewrite;
 
 	$queried_object    = $wp_query->get_queried_object();
diff --git a/src/wp-includes/pomo/entry.php b/src/wp-includes/pomo/entry.php
index e1b1c8f8c8..48c52384b1 100644
--- a/src/wp-includes/pomo/entry.php
+++ b/src/wp-includes/pomo/entry.php
@@ -114,7 +114,7 @@ if ( ! class_exists( 'Translation_Entry', false ) ) :
 		 *
 		 * @param Translation_Entry $other Other translation entry.
 		 */
-		public function merge_with( &$other ) {
+		public function merge_with( $other ) {
 			$this->flags      = array_unique( array_merge( $this->flags, $other->flags ) );
 			$this->references = array_unique( array_merge( $this->references, $other->references ) );
 			if ( $this->extracted_comments !== $other->extracted_comments ) {
diff --git a/src/wp-includes/pomo/po.php b/src/wp-includes/pomo/po.php
index de1bc92064..594ad80f4e 100644
--- a/src/wp-includes/pomo/po.php
+++ b/src/wp-includes/pomo/po.php
@@ -486,7 +486,7 @@ if ( ! class_exists( 'PO', false ) ) :
 		 * @param Translation_Entry $entry
 		 * @param string            $po_comment_line
 		 */
-		public function add_comment_to_entry( &$entry, $po_comment_line ) {
+		public function add_comment_to_entry( $entry, $po_comment_line ) {
 			$first_two = substr( $po_comment_line, 0, 2 );
 			$comment   = trim( substr( $po_comment_line, 2 ) );
 			if ( '#:' === $first_two ) {
diff --git a/src/wp-includes/pomo/translations.php b/src/wp-includes/pomo/translations.php
index c4a9ba72d6..8d1a2183b9 100644
--- a/src/wp-includes/pomo/translations.php
+++ b/src/wp-includes/pomo/translations.php
@@ -130,7 +130,7 @@ if ( ! class_exists( 'Translations', false ) ) :
 		 * @param Translation_Entry $entry Translation entry.
 		 * @return Translation_Entry|false Translation entry if it exists, false otherwise.
 		 */
-		public function translate_entry( &$entry ) {
+		public function translate_entry( $entry ) {
 			$key = $entry->key();
 			return $this->entries[ $key ] ?? false;
 		}
@@ -220,9 +220,9 @@ if ( ! class_exists( 'Translations', false ) ) :
 		 *
 		 * @since 2.8.0
 		 *
-		 * @param Translations $other Another Translation object, whose translations will be merged in this one (passed by reference).
+		 * @param Translations $other Another Translation object, whose translations will be merged in this one.
 		 */
-		public function merge_with( &$other ) {
+		public function merge_with( $other ) {
 			foreach ( $other->entries as $entry ) {
 				$this->entries[ $entry->key() ] = $entry;
 			}
@@ -235,7 +235,7 @@ if ( ! class_exists( 'Translations', false ) ) :
 		 *
 		 * @param Translations $other
 		 */
-		public function merge_originals_with( &$other ) {
+		public function merge_originals_with( $other ) {
 			foreach ( $other->entries as $entry ) {
 				if ( ! isset( $this->entries[ $entry->key() ] ) ) {
 					$this->entries[ $entry->key() ] = $entry;
diff --git a/src/wp-includes/post.php b/src/wp-includes/post.php
index f4b06958e0..cb7a91d56c 100644
--- a/src/wp-includes/post.php
+++ b/src/wp-includes/post.php
@@ -6309,10 +6309,10 @@ function get_page_hierarchy( $pages, $page_id = 0 ) {
  * @see _page_traverse_name()
  *
  * @param int      $page_id  Page ID.
- * @param array    $children Parent-children relations (passed by reference).
+ * @param array    $children Parent-children relations.
  * @param string[] $result   Array of page names keyed by ID (passed by reference).
  */
-function _page_traverse_name( $page_id, &$children, &$result ) {
+function _page_traverse_name( $page_id, $children, &$result ) {
 	if ( isset( $children[ $page_id ] ) ) {
 		foreach ( (array) $children[ $page_id ] as $child ) {
 			$result[ $child->ID ] = $child->post_name;
@@ -7678,9 +7678,9 @@ function _get_last_post_time( $timezone, $field, $post_type = 'any' ) {
  *
  * @since 1.5.1
  *
- * @param WP_Post[] $posts Array of post objects (passed by reference).
+ * @param WP_Post[] $posts Array of post objects.
  */
-function update_post_cache( &$posts ) {
+function update_post_cache( $posts ) {
 	if ( ! $posts ) {
 		return;
 	}
@@ -7762,12 +7762,12 @@ function clean_post_cache( $post ) {
  *
  * @since 1.5.0
  *
- * @param WP_Post[] $posts             Array of post objects (passed by reference).
+ * @param WP_Post[] $posts             Array of post objects.
  * @param string    $post_type         Optional. Post type. Default 'post'.
  * @param bool      $update_term_cache Optional. Whether to update the term cache. Default true.
  * @param bool      $update_meta_cache Optional. Whether to update the meta cache. Default true.
  */
-function update_post_caches( &$posts, $post_type = 'post', $update_term_cache = true, $update_meta_cache = true ) {
+function update_post_caches( $posts, $post_type = 'post', $update_term_cache = true, $update_meta_cache = true ) {
 	// No point in doing all this work if we didn't match any posts.
 	if ( ! $posts ) {
 		return;