Add aria-label toggling for play/pause and fill browser buttons

common/lib/xmodule/xmodule/js/src/video/04_video_full_screen.js

@@ -136,7 +136,7 @@
             fullScreenClassNameEl.removeClass('video-fullscreen');
             $(window).scrollTop(this.scrollPos);
             this.videoFullScreen.fullScreenEl
-            .attr('title', gettext('Fill browser'))
+            .attr({title: gettext('Fill browser'), 'aria-label': gettext('Fill browser')})
             .find('.icon')
                 .removeClass('fa-compress')
                 .addClass('fa-arrows-alt');
@@ -158,7 +158,7 @@
             this.videoFullScreen.fullScreenState = this.isFullScreen = true;
             fullScreenClassNameEl.addClass('video-fullscreen');
             this.videoFullScreen.fullScreenEl
-            .attr('title', gettext('Exit full browser'))
+            .attr({title: gettext('Exit full browser'), 'aria-label': gettext('Exit full browser')})
             .find('.icon')
                 .removeClass('fa-arrows-alt')
                 .addClass('fa-compress');

common/lib/xmodule/xmodule/js/src/video/09_play_pause_control.js

@@ -74,7 +74,7 @@
                 this.el
                 .addClass('pause')
                 .removeClass('play')
-                .attr('title', gettext('Pause'))
+                .attr({title: gettext('Pause'), 'aria-label': gettext('Pause')})
                 .find('.icon')
                     .removeClass('fa-play')
                     .addClass('fa-pause');
@@ -84,7 +84,7 @@
                 this.el
                 .removeClass('pause')
                 .addClass('play')
-                .attr('title', gettext('Play'))
+                .attr({title: gettext('Play'), 'aria-label': gettext('Play')})
                 .find('.icon')
                     .removeClass('fa-pause')
                     .addClass('fa-play');