Bring back crossed eye icon on gallery (mastodon#10715)

Author: tribela

app/javascript/mastodon/features/account_gallery/components/media_item.js

@@ -2,6 +2,7 @@ import React from 'react';
 import PropTypes from 'prop-types';
 import ImmutablePropTypes from 'react-immutable-proptypes';
 import ImmutablePureComponent from 'react-immutable-pure-component';
+import Icon from 'mastodon/components/icon';
 import { autoPlayGif, displayMedia } from 'mastodon/initial_state';
 import classNames from 'classnames';
 import { decode } from 'blurhash';
@@ -91,6 +92,7 @@ export default class MediaItem extends ImmutablePureComponent {
     const title = status.get('spoiler_text') || attachment.get('description');
 
     let thumbnail = '';
+    let icon;
 
     if (attachment.get('type') === 'unknown') {
       // Skip
@@ -132,11 +134,20 @@ export default class MediaItem extends ImmutablePureComponent {
       );
     }
 
+    if (!visible) {
+      icon = (
+        <span className='account-gallery__item__icons'>
+          <Icon id='eye-slash' />
+        </span>
+      );
+    }
+
     return (
       <div className='account-gallery__item' style={{ width, height }}>
         <a className='media-gallery__item-thumbnail' href={status.get('url')} target='_blank' onClick={this.handleClick} title={title}>
           <canvas width={32} height={32} ref={this.setCanvasRef} className={classNames('media-gallery__preview', { 'media-gallery__preview--hidden': visible && loaded })} />
           {visible && thumbnail}
+          {!visible && icon}
         </a>
       </div>
     );

app/javascript/styles/mastodon/components.scss

@@ -4829,6 +4829,14 @@ a.status-card.compact:hover {
   border-radius: 4px;
   overflow: hidden;
   margin: 2px;
+
+  &__icons {
+    position: absolute;
+    top: 50%;
+    left: 50%;
+    transform: translate(-50%, -50%);
+    font-size: 24px;
+  }
 }
 
 .notification__filter-bar,