local ntp: fix up accessibility tree

chrome/browser/resources/local_ntp/most_visited_single.js

Index: chrome/browser/resources/local_ntp/most_visited_single.js
diff --git a/chrome/browser/resources/local_ntp/most_visited_single.js b/chrome/browser/resources/local_ntp/most_visited_single.js
index 89b6adfd2d03ddb1ee696f29e6b1c8eb5acbebb8..e2e0911eb43557e4178920adaf9de2185fcbb191 100644
--- a/chrome/browser/resources/local_ntp/most_visited_single.js
+++ b/chrome/browser/resources/local_ntp/most_visited_single.js
@@ -379,13 +379,14 @@ var renderTile = function(data) {
     html.push('<div class="mv-favicon"></div>');
   }
   html.push('<div class="mv-title"></div><div class="mv-thumb"></div>');
-  html.push('<div class="mv-x"></div>');
+  html.push('<div class="mv-x" role="button"></div>');
   tile.innerHTML = html.join('');
   tile.lastElementChild.title = queryArgs['removeTooltip'] || '';
 
   if (isSchemeAllowed(data.url)) {
     tile.href = data.url;
   }
+  tile.setAttribute('aria-label', data.title);
   tile.title = data.title;
   if (data.impressionUrl) {
     impressionUrl = data.impressionUrl;