Twenty Nineteen: Improve custom color behavior for InnerBlocks

Currently, if a parent block has a custom background color assigned, its child blocks will inherit the parent's text colors — even if the child block has its own custom text color assigned to it. 

This update changes the following: 

- Adjusts Twenty Nineteen's custom background color defaults to target direct children only which fixes the issue

Props kjellr.

See #46432.


Built from https://develop.svn.wordpress.org/trunk@44818


git-svn-id: http://core.svn.wordpress.org/trunk@44650 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.2-alpha-44816';
+$wp_version = '5.2-alpha-44818';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.