Twenty Seventeen: Fix style issues with gallery image links

* Ensures dark color scheme has proper box shadow and hover/focus styles.
* Make sure links are correct width.

Props afercia, laurelfulford.

Fixes #38969.

Built from https://develop.svn.wordpress.org/trunk@39418


git-svn-id: http://core.svn.wordpress.org/trunk@39358 1a063a9b-81f0-0310-95a4-ce76da25c4cd

wp-content/themes/twentyseventeen/assets/css/colors-dark.css

@@ -474,8 +474,8 @@ body.colors-dark,
 }
 
 /* Fixes linked images */
-.entry-content a img,
-.widget a img {
+.colors-dark .entry-content a img,
+.colors-dark .widget a img {
 	-webkit-box-shadow: 0 0 0 8px #222;
 	box-shadow: 0 0 0 8px #222;
 }
@@ -496,6 +496,9 @@ body.colors-dark,
 	background-color: transparent;
 }
 
+.colors-dark .gallery-item a,
+.colors-dark .gallery-item a:hover,
+.colors-dark .gallery-item a:focus,
 .colors-dark .widget .tagcloud a,
 .colors-dark .widget .tagcloud a:focus,
 .colors-dark .widget .tagcloud a:hover,

wp-content/themes/twentyseventeen/style.css

@@ -2952,7 +2952,7 @@ object {
 	box-shadow: none;
 	background: none;
 	display: inline-block;
-	width: 100%;
+	max-width: 100%;
 }
 
 .gallery-item a img {

wp-includes/version.php

@@ -4,7 +4,7 @@
  *
  * @global string $wp_version
  */
-$wp_version = '4.8-alpha-39417';
+$wp_version = '4.8-alpha-39418';
 
 /**
  * Holds the WordPress DB revision, increments when changes are made to the WordPress DB schema.