[Glitch] Add lang attribute to media and poll options

Port d3eefead30 to glitch-soc

Signed-off-by: Claire <claire.github-309c@sitedethib.com>

app/javascript/flavours/glitch/features/audio/index.jsx

@@ -28,6 +28,7 @@ class Audio extends React.PureComponent {
   static propTypes = {
     src: PropTypes.string.isRequired,
     alt: PropTypes.string,
+    lang: PropTypes.string,
     poster: PropTypes.string,
     duration: PropTypes.number,
     width: PropTypes.number,
@@ -464,7 +465,7 @@ class Audio extends React.PureComponent {
   };
 
   render () {
-    const { src, intl, alt, editable, autoPlay, sensitive, blurhash } = this.props;
+    const { src, intl, alt, lang, editable, autoPlay, sensitive, blurhash } = this.props;
     const { paused, muted, volume, currentTime, duration, buffer, dragging, revealed } = this.state;
     const progress = Math.min((currentTime / duration) * 100, 100);
 
@@ -509,6 +510,7 @@ class Audio extends React.PureComponent {
           onKeyDown={this.handleAudioKeyDown}
           title={alt}
           aria-label={alt}
+          lang={lang}
         />
 
         <div className={classNames('spoiler-button', { 'spoiler-button--hidden': revealed || editable })}>