Twenty Twenty-One: Only enqueue block editor assets in the admin.

Follow-up to [56300].

Props sabernhardt, flixos90, luisherranz, gautam23, huzaifaalmesbah, mukesh27, r1k0, SergeyBiryukov.
Fixes #60111.

git-svn-id: https://develop.svn.wordpress.org/trunk@61471 602fd350-edb4-49c9-b593-d223f7449a82

Author: SergeyBiryukov

src/wp-content/themes/twentytwentyone/classes/class-twenty-twenty-one-custom-colors.php

@@ -23,7 +23,9 @@ public function __construct() {
 		add_action( 'wp_enqueue_scripts', array( $this, 'custom_color_variables' ) );
 
 		// Enqueue color variables for editor.
-		add_action( 'enqueue_block_assets', array( $this, 'editor_custom_color_variables' ) );
+		if ( is_admin() ) {
+			add_action( 'enqueue_block_assets', array( $this, 'editor_custom_color_variables' ) );
+		}
 
 		// Add body-class if needed.
 		add_filter( 'body_class', array( $this, 'body_class' ) );

src/wp-content/themes/twentytwentyone/classes/class-twenty-twenty-one-dark-mode.php

@@ -20,7 +20,9 @@ class Twenty_Twenty_One_Dark_Mode {
 	public function __construct() {
 
 		// Enqueue assets for the block-editor.
-		add_action( 'enqueue_block_assets', array( $this, 'editor_custom_color_variables' ) );
+		if ( is_admin() ) {
+			add_action( 'enqueue_block_assets', array( $this, 'editor_custom_color_variables' ) );
+		}
 
 		// Add styles for dark-mode.
 		add_action( 'wp_enqueue_scripts', array( $this, 'enqueue_scripts' ) );