Block Editor: Update WordPress Packages WordPress 5.4 RC 5.

The following package versions were changed:
@wordpress/annotations: 1.12.2 -> 1.12.3
@wordpress/block-directory: 1.5.6 -> 1.5.7
@wordpress/block-editor: 3.7.6 -> 3.7.7
@wordpress/block-library: 2.14.6 -> 2.14.7
@wordpress/blocks: 6.12.2 -> 6.12.3
@wordpress/components: 9.2.5 -> 9.2.6
@wordpress/core-data: 2.12.2 -> 2.12.3
@wordpress/edit-post: 3.13.7 -> 3.13.8
@wordpress/editor: 9.12.6 -> 9.12.7
@wordpress/format-library: 1.14.6 -> 1.14.7
@wordpress/list-reusable-blocks: 1.13.5 -> 1.13.6
@wordpress/nux: 3.12.5 -> 3.12.6
@wordpress/server-side-render: 1.8.5 -> 1.8.6
Description of editor changes included in the RC available at WordPress/gutenberg#21210.

Props mcsf, aduth.
Merges [47513] to the 5.4 branch.
Fixes: #49716.
Built from https://develop.svn.wordpress.org/branches/5.4@47514

wp-includes/js/dist/annotations.js

@@ -1176,14 +1176,15 @@ var external_this_wp_hooks_ = __webpack_require__(32);
 
 var block_addAnnotationClassName = function addAnnotationClassName(OriginalComponent) {
   return Object(external_this_wp_data_["withSelect"])(function (select, _ref) {
-    var clientId = _ref.clientId;
+    var clientId = _ref.clientId,
+        className = _ref.className;
 
     var annotations = select('core/annotations').__experimentalGetAnnotationsForBlock(clientId);
 
     return {
       className: annotations.map(function (annotation) {
         return 'is-annotated-by-' + annotation.source;
-      }).join(' ')
+      }).concat(className).filter(Boolean).join(' ')
     };
   })(OriginalComponent);
 };

wp-includes/js/dist/blocks.js

@@ -10846,9 +10846,6 @@ var embeddedContentSchema = {
   embed: {
     attributes: ['src', 'type', 'width', 'height']
   },
-  iframe: {
-    attributes: ['src', 'srcdoc', 'name', 'sandbox', 'seamless', 'width', 'height']
-  },
   img: {
     attributes: ['alt', 'src', 'srcset', 'usemap', 'ismap', 'width', 'height']
   },

wp-includes/js/dist/components.js

@@ -9461,7 +9461,7 @@ function useSlotRegistry() {
       // See https://github.com/WordPress/gutenberg/pull/19242#issuecomment-590295412
 
 
-      if (slot.ref === ref) {
+      if ((slot === null || slot === void 0 ? void 0 : slot.ref) === ref) {
         return nextSlots;
       }
 

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.4-RC4-47505';
+$wp_version = '5.4-RC4-47514';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.