Remove bug_hash which is no longer used

core/bug_api.php

@@ -978,40 +978,6 @@ function bug_text_clear_cache( $p_bug_id = null ) {
 	return true;
 }
 
-/**
- * Get hash for the bug information.  Used in scenarios like ETag for REST API.
- * A proper hash will be returned even if the issue doesn't exist.
- *
- * @param integer $p_bug_id The bug id.
- * @param integer|null $p_user_id The user id or null for current logged in user.
- * @return string The hash.
- */
-function bug_hash( $p_bug_id, $p_user_id = null ) {
-	# This is needed for cases where a bug has been updated, and a new hash is to be calculated.
-	bug_clear_cache( $p_bug_id );
-
-	# Change this version when it is desired to force clients to refresh issues.
-	$t_version = 'v1';
-
-	if( auth_is_user_authenticated() ) {
-		$t_user_id = $p_user_id ? (int)$p_user_id : auth_get_current_user_id();
-	} else {
-		$t_user_id = $p_user_id ?: '';
-	}
-
-	if( bug_exists( $p_bug_id ) ) {
-		$t_bug_data = bug_get( $p_bug_id, false );
-		$t_last_updated = $t_bug_data->last_updated;
-	} else {
-		$t_last_updated = '';
-	}
-
-	$t_bug_id = (int)$p_bug_id;
-
-	$t_str_to_hash = $t_bug_id . '_' . $t_last_updated . '_' . $t_user_id . '_' . $t_version;
-	return hash( 'sha256', $t_str_to_hash );
-}
-
 /**
  * Check if a bug exists
  * @param integer $p_bug_id Integer representing bug identifier.