Support text track selection in video controls

Source/core/css/mediaControls.css

 /*
  * Copyright (C) 2009 Apple Inc.  All rights reserved.
  * Copyright (C) 2009 Google Inc.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
@@ skipping 312 matching lines @@
     width: 30px;
     height: 30px;
     line-height: 30px;
     margin-left: -5px;
     margin-right: 9px;
     padding: 0;
     background-color: initial;
     color: inherit;
 }
 
+video::-webkit-media-controls-text-track-list-container {
+    position: absolute;
+    display: block;
+    bottom: 30px;
+    background: rgba(20, 20, 20, 0.8);
+    max-width: 50%;
+    max-height: 250px;
+    right: 0;
+    border-radius: 5px;
+    overflow-x: hidden;
+    overflow-y: auto;
+    text-overflow: ellipsis;
+    bottom: 100%;
+    margin-bottom: 5px;
+    font-family: Arial, Helvetica, sans-serif;
+    white-space: nowrap;
+}
+
+video::-webkit-scrollbar {
+    width: 12px;
+}
+
+video::-webkit-scrollbar-track {
+    box-shadow: inset 0 0 6px rgba(20, 20, 20, 0.3);
+    border-radius: 10px;
+}
+
+video::-webkit-scrollbar-thumb {
+    border-radius: 10px;
+    background-color: rgba(80, 80, 80, 0.8);
+    box-shadow: inset 0 0 6px rgba(20, 20, 20, 0.5);
+}
+
+video::-webkit-media-controls-text-track-list {
+    display: block;
+    padding: 10px;
+    font-weight: bold;
+    font-size: 16px;
+}
+
+video::-webkit-media-controls-text-track-list-header {
+    margin: 0;
+    text-shadow: 0 1px 0 black;
+    text-align: center;
+    color: gray;
+    padding: 4px 0 4px 4px;
+    border-bottom: 1px solid #555;
+}
+
+video::-webkit-media-controls-text-track-list-item {
+    display: block;
+    color: white;
+    padding: 4px 30px 4px 30px;
+    border-bottom: 1px solid #555;
+    text-align: left;
+    position: relative;
+    line-height: 25px;
+}
+
+video::-webkit-media-controls-text-track-list-item:hover {
+    background-color: rgba(105, 105, 105, 0.8);
+}
+
+video::-webkit-media-controls-text-track-list-item-input {
+    -webkit-appearance: media-track-selection-checkmark;
+    position: absolute;
+    visibility: hidden;
+    top: 4px;
+    left: 0;
+    margin: 0;
+    width: 25px;
+    height: 25px;
+}
+
+video::-webkit-media-controls-text-track-list-item-input:checked {
+    visibility: visible;
+}
+
 audio::-webkit-media-controls-fullscreen-volume-slider, video::-webkit-media-controls-fullscreen-volume-slider {
     display: none;
 }
 
 audio::-webkit-media-controls-fullscreen-volume-min-button, video::-webkit-media-controls-fullscreen-volume-min-button {
     display: none;
 }
 
 audio::-webkit-media-controls-fullscreen-volume-max-button, video::-webkit-media-controls-fullscreen-volume-max-button {
     display: none;
@@ skipping 66 matching lines @@
     font-weight: bold;
 }
 
 video::-webkit-media-text-track-container u {
     text-decoration: underline;
 }
 
 video::-webkit-media-text-track-container i {
     font-style: italic;
 }