Issue #2655772 by Anishnirmal, andrewmacpherson, pbuyle, BarisW, mgifford,...

Issue #2655772 by Anishnirmal, andrewmacpherson, pbuyle, BarisW, mgifford, LaravZ: Remove unneeded role="button" attribute from <button> elements

core/modules/ckeditor/js/ckeditor.admin.js

@@ -493,7 +493,7 @@
    *   A HTML string for the button to create a name for a new button group.
    */
   Drupal.theme.ckeditorNewButtonGroup = function () {
-    return '<li class="ckeditor-add-new-group"><button role="button" aria-label="' + Drupal.t('Add a CKEditor button group to the end of this row.') + '">' + Drupal.t('Add group') + '</button></li>';
+    return '<li class="ckeditor-add-new-group"><button aria-label="' + Drupal.t('Add a CKEditor button group to the end of this row.') + '">' + Drupal.t('Add group') + '</button></li>';
   };
 
 })(jQuery, Drupal, drupalSettings, _);

core/modules/contextual/contextual.module

@@ -35,7 +35,6 @@ function contextual_toolbar() {
       '#value' => t('Edit'),
       '#attributes' => array(
         'class' => array('toolbar-icon', 'toolbar-icon-edit'),
-        'role' => 'button',
         'aria-pressed' => 'false',
       ),
     ),

core/modules/tour/tour.module

@@ -53,7 +53,6 @@ function tour_toolbar() {
       '#value' => t('Tour'),
       '#attributes' => array(
         'class' => array('toolbar-icon', 'toolbar-icon-help'),
-        'role' => 'button',
         'aria-pressed' => 'false',
       ),
     ),