General: Remove “whitelist” and “blacklist” in favor of more clear and inclusive language.

“The WordPress open source community cares about diversity. We strive to maintain a welcoming environment where everyone can feel included.”

With this commit, all occurrences of “whitelist” and “blacklist” (with the single exception of the `$new_whitelist_options` global variable) are removed. A new ticket has been opened to explore renaming the `$new_whitelist_options` variable (#50434).

Changing to more specific names or rewording sentences containing these terms not only makes the code more inclusive, but also helps provide clarity. These terms are often ambiguous. What is being blocked or allowed is not always immediately clear. This can make it more difficult for non-native English speakers to read through the codebase.

Words matter. If one contributor feels more welcome because these terms are removed, this was worth the effort.

Props strangerstudios, jorbin, desrosj, joemcgill, timothyblynjacobs, ocean90, ayeshrajans, davidbaumwald, earnjam.
See #48900, #50434.
Fixes #50413.

git-svn-id: https://develop.svn.wordpress.org/trunk@48121 602fd350-edb4-49c9-b593-d223f7449a82

src/wp-includes/http.php

@@ -593,7 +593,7 @@ function wp_http_validate_url( $url ) {
 }
 
 /**
- * Whitelists allowed redirect hosts for safe HTTP requests as well.
+ * Mark allowed redirect hosts safe for HTTP requests as well.
  *
  * Attached to the {@see 'http_request_host_is_external'} filter.
  *
@@ -611,7 +611,8 @@ function allowed_http_request_hosts( $is_external, $host ) {
 }
 
 /**
- * Whitelists any domain in a multisite installation for safe HTTP requests.
+ * Adds any domain in a multisite installation for safe HTTP requests to the
+ * allowed list.
  *
  * Attached to the {@see 'http_request_host_is_external'} filter.
  *