Build/Test: Bump Autoprefixer to 6.5.0

Also includes a new prefixed value.

Changes:
6.5 “Einigkeit und Recht und Freiheit”
- Add defaults keyword to browsers requirements.
- Fix CSS Grid Layout support.
- Fix align-self cleaning.

6.4.1
- Fix node cloning after some PostCSS plugins.

6.4 “Hic et ubique terrarum”
- Add :any-link selector support.
- Add text-decoration-skip support.
- Add transition: duration property support.
- Fix -webkit- prefix for backface-visibility.
- Fix rad unit support in gradients (by 刘祺).
- Fix transition support in Opera 12.
- Removed Safari TP Grid prefixes support.

6.3.7
- Fix rare Cannot read property 'constructor' of null issue.

6.3.6
- Add Safari TP prefix support for Grid Layout.

6.3.5
- Fix duplicate prefixes for -ms-interpolation-mode.

6.3.4
- Show users coverage for selected browsers in info().

28.0
- Happy Birthday @nacin

See #38199



Built from https://develop.svn.wordpress.org/trunk@38688


git-svn-id: http://core.svn.wordpress.org/trunk@38631 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-admin/css/customize-nav-menus-rtl.css

@@ -568,6 +568,7 @@
 }
 
 #available-menu-items .accordion-section-content .new-content-item {
+	width: -webkit-calc(100% - 30px);
 	width: calc(100% - 30px);
 	padding: 8px 15px;
 	position: absolute;

wp-admin/css/customize-nav-menus.css

@@ -568,6 +568,7 @@
 }
 
 #available-menu-items .accordion-section-content .new-content-item {
+	width: -webkit-calc(100% - 30px);
 	width: calc(100% - 30px);
 	padding: 8px 15px;
 	position: absolute;

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.7-alpha-38687';
+$wp_version = '4.7-alpha-38688';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.