Index: src/wp-includes/formatting.php
===================================================================
--- src/wp-includes/formatting.php	(revision 36223)
+++ src/wp-includes/formatting.php	(working copy)
@@ -4532,7 +4532,7 @@
 		 *
 		 * @param string The emoji base URL.
 		 */
-		'baseUrl' => apply_filters( 'emoji_url', set_url_scheme( '//s.w.org/images/core/emoji/72x72/' ) ),
+		'baseUrl' => apply_filters( 'emoji_url', 'https://s.w.org/images/core/emoji/72x72/' ),
 
 		/**
 		 * Filter the extension of the emoji files.
@@ -4644,7 +4644,7 @@
 	$text = wp_encode_emoji( $text );
 
 	/** This filter is documented in wp-includes/formatting.php */
-	$cdn_url = apply_filters( 'emoji_url', set_url_scheme( '//s.w.org/images/core/emoji/72x72/' ) );
+	$cdn_url = apply_filters( 'emoji_url', 'https://s.w.org/images/core/emoji/72x72/' );
 
 	/** This filter is documented in wp-includes/formatting.php */
 	$ext = apply_filters( 'emoji_ext', '.png' );