Widgets: Pass correct context to `get_block_categories()` calls.

The `get_block_categories()` function expects either a `WP_Post` or a `WP_Block_Editor_Context` instance as the context argument, not a string.

Follow-up to [50996], [50997].

Props Enchiridion, pbearne, audrasjb, SergeyBiryukov.
Merges [51700] to the 5.8 branch.
Fixes #53757.
Built from https://develop.svn.wordpress.org/branches/5.8@51711


git-svn-id: http://core.svn.wordpress.org/branches/5.8@51317 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/widgets-form-blocks.php

@@ -52,7 +52,7 @@ wp_add_inline_script(
 
 wp_add_inline_script(
 	'wp-blocks',
-	sprintf( 'wp.blocks.setCategories( %s );', wp_json_encode( get_block_categories( 'widgets-editor' ) ) ),
+	sprintf( 'wp.blocks.setCategories( %s );', wp_json_encode( get_block_categories( $block_editor_context ) ) ),
 	'after'
 );
 

wp-includes/class-wp-customize-widgets.php

@@ -862,7 +862,7 @@ final class WP_Customize_Widgets {
 
 			wp_add_inline_script(
 				'wp-blocks',
-				sprintf( 'wp.blocks.setCategories( %s );', wp_json_encode( get_block_categories( 'widgets-customizer' ) ) ),
+				sprintf( 'wp.blocks.setCategories( %s );', wp_json_encode( get_block_categories( $block_editor_context ) ) ),
 				'after'
 			);
 

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.8.1-alpha-51710';
+$wp_version = '5.8.1-alpha-51711';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.