About page: Remove `autoplay` and `loop` attributes on "Theme Starter Content", "Edit Shortcuts", and "Video Headers" videos, originally added as a part of [39512].

For UX and accessibility reasons, it's better to always avoid playing videos automatically.

Props bor0.
Fixes #39560.
Built from https://develop.svn.wordpress.org/trunk@40089


git-svn-id: http://core.svn.wordpress.org/trunk@40026 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/about.php

@@ -78,8 +78,6 @@ include( ABSPATH . 'wp-admin/admin-header.php' );
 				echo wp_video_shortcode( array(
 					'mp4'      => 'https://s.w.org/images/core/4.7/starter-content-v1.mp4',
 					'poster'   => 'https://s.w.org/images/core/4.7/starter-content.jpg?v2',
-					'loop'     => true,
-					'autoplay' => true,
 					'width'    => 1140,
 					'height'   => 624,
 					// 'class'    => 'wp-video-shortcode feature-video',
@@ -95,8 +93,6 @@ include( ABSPATH . 'wp-admin/admin-header.php' );
 				echo wp_video_shortcode( array(
 					'mp4'      => 'https://s.w.org/images/core/4.7/edit-shortcuts-v1.mp4',
 					'poster'   => 'https://s.w.org/images/core/4.7/edit-shortcuts.jpg?v2',
-					'loop'     => true,
-					'autoplay' => true,
 					'width'    => 2520,
 					'height'   => 1454,
 					// 'class'    => 'wp-video-shortcode feature-video',
@@ -110,8 +106,6 @@ include( ABSPATH . 'wp-admin/admin-header.php' );
 				echo wp_video_shortcode( array(
 					'mp4'      => 'https://s.w.org/images/core/4.7/header-video-v1.mp4',
 					'poster'   => 'https://s.w.org/images/core/4.7/header-video.jpg?v2',
-					'loop'     => true,
-					'autoplay' => true,
 					'width'    => 2520,
 					'height'   => 1454,
 					// 'class'    => 'wp-video-shortcode feature-video',

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.8-alpha-40086';
+$wp_version = '4.8-alpha-40089';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.