Media: in `wp_get_attachment_image_sizes()`, ensure that `$img_width` exists when the image does not.

Props kraftbj.
See #33641.


Built from https://develop.svn.wordpress.org/trunk@35250


git-svn-id: http://core.svn.wordpress.org/trunk@35216 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/media.php

@@ -1003,12 +1003,12 @@ function wp_get_attachment_image_srcset( $attachment_id, $size = 'medium' ) {
  * @return string|bool A valid source size value for use in a 'sizes' attribute or false.
  */
 function wp_get_attachment_image_sizes( $attachment_id, $size = 'medium', $args = null ) {
-
+	$img_width = 0;
 	// Try to get the image width from $args.
 	if ( is_array( $args ) && ! empty( $args['width'] ) ) {
 		$img_width = (int) $args['width'];
 	} elseif ( $img = image_get_intermediate_size( $attachment_id, $size ) ) {
-		list( $img_width, $img_height ) = image_constrain_size_for_editor( $img['width'], $img['height'], $size );
+		list( $img_width ) = image_constrain_size_for_editor( $img['width'], $img['height'], $size );
 	}
 
 	// Bail early if $image_width isn't set.

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4-alpha-35249';
+$wp_version = '4.4-alpha-35250';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.