Media: `media_handle_sideload()` expectes `wp_insert_attachment()` to return a `WP_Error`.

For `wp_insert_attachment()` to do that, we need to be setting the `$wp_error` parameter to true.

Props subrataemfluence, jirihon.
Fixes #44303.


Built from https://develop.svn.wordpress.org/trunk@44634


git-svn-id: http://core.svn.wordpress.org/trunk@44465 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/includes/media.php

@@ -467,7 +467,7 @@ function media_handle_sideload( $file_array, $post_id, $desc = null, $post_data
 	unset( $attachment['ID'] );
 
 	// Save the attachment metadata
-	$id = wp_insert_attachment( $attachment, $file, $post_id );
+	$id = wp_insert_attachment( $attachment, $file, $post_id, true );
 	if ( ! is_wp_error( $id ) ) {
 		wp_update_attachment_metadata( $id, wp_generate_attachment_metadata( $id, $file ) );
 	}

wp-includes/version.php

@@ -13,7 +13,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '5.1-beta1-44633';
+$wp_version = '5.1-beta1-44634';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.