MD Bookmarks: Initial screenreader accessibility improvements

chrome/browser/resources/md_bookmarks/item.html

 <link rel="import" href="chrome://resources/html/polymer.html">
 
 <link rel="import" href="chrome://resources/cr_elements/icons.html">
 <link rel="import" href="chrome://resources/html/icon.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/iron-icon/iron-icon.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button-light.html">
 <link rel="import" href="chrome://bookmarks/actions.html">
 <link rel="import" href="chrome://bookmarks/mouse_focus_behavior.html">
 <link rel="import" href="chrome://bookmarks/shared_style.html">
 <link rel="import" href="chrome://bookmarks/store_client.html">
@@ skipping 50 matching lines @@
     </style>
     <div id="url">
       <div id="icon-wrapper">
         <iron-icon id="folder-icon" icon="cr:folder" hidden$="[[!isFolder_]]">
         </iron-icon>
         <div id="icon" hidden$="[[isFolder_]]"></div>
       </div>
       <div id="website-title">
         [[item_.title]]
       </div>
-      <button is="paper-icon-button-light" class="more-vert-button"
-          on-click="onMenuButtonClick_" on-dblclick="onMenuButtonDblClick_"
-          tabindex$="[[ironListTabIndex]]" on-focus="clearMouseFocus">
+      <button is="paper-icon-button-light"
+          class="more-vert-button"
+          tabindex$="[[ironListTabIndex]]"
+          title="$i18n{moreActionsButtonTitle}"
+          on-click="onMenuButtonClick_"
+          on-dblclick="onMenuButtonDblClick_"
+          on-focus="clearMouseFocus">
         <div></div>
         <div></div>
         <div></div>
       </button>
     </div>
   </template>
   <script src="chrome://bookmarks/item.js"></script>
 <dom-module>