Media: Add a new function, `wp_get_attachment_image_url()`, which is a shortcut for `wp_get_attachment_image_src()` - same function signature, but returns just the URL based on `$size`.

Adds unit test.

Props dipesh.kakadiya, swissspidy, sebastian.pisula.
Fixes #33878.

Built from https://develop.svn.wordpress.org/trunk@34372


git-svn-id: http://core.svn.wordpress.org/trunk@34336 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-includes/media.php

@@ -793,6 +793,22 @@ function wp_get_attachment_image($attachment_id, $size = 'thumbnail', $icon = fa
 	return $html;
 }
 
+/**
+ * Get the URL of an image attachment.
+ *
+ * @since 4.4.0
+ *
+ * @param int          $attachment_id Image attachment ID.
+ * @param string|array $size          Optional. Registered image size to retrieve the source for or a flat
+ *                                    array of height and width dimensions. Default 'thumbnail'.
+ * @param bool         $icon          Optional. Whether the image should be treated as an icon. Default false.
+ * @return string|false Attachment URL or false if no image is available.
+ */
+function wp_get_attachment_image_url( $attachment_id, $size = 'thumbnail', $icon = false ) {
+	$image = wp_get_attachment_image_src( $attachment_id, $size, $icon );
+	return isset( $image['0'] ) ? $image['0'] : false;
+}
+
 /**
  * Adds a 'wp-post-image' class to post thumbnails. Internal use only.
  *

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.4-alpha-34371';
+$wp_version = '4.4-alpha-34372';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.