MD Settings: Network a11y fixes

chrome/browser/resources/settings/internet_page/network_nameservers.html

 <link rel="import" href="chrome://resources/cr_elements/network/cr_onc_types.html">
 <link rel="import" href="chrome://resources/html/md_select_css.html">
 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-input/paper-input-container.html">
 <link rel="import" href="../settings_vars_css.html">
 <link rel="import" href="internet_shared_css.html">
 
 <dom-module id="network-nameservers">
   <template>
     <style include="internet-shared md-select">
       paper-input-container {
         -webkit-padding-start: 4px;
       }
     </style>
 
     <div class="settings-box first">
       <div class="start">$i18n{networkSectionNameservers}</div>
       <div class="md-select-wrapper">
         <select id="nameserverType" class="md-select" on-change="onTypeChange_"
-            value="[[nameserversType_]]">
+            value="[[nameserversType_]]"
+            aria-label="$i18n{networkSectionNameservers}">
           <template is="dom-repeat" items="[[nameserverTypeNames_]]">
             <option value="[[item]]">[[nameserverTypeDesc_(item)]]</option>
           </template>
         </select>
         <span class="md-select-underline"></span>
       </div>
     </div>
 
     <div class="settings-box continuation single-column"
         hidden$="[[!nameservers_.length]]">
       <template is="dom-repeat" items="[[nameservers_]]">
         <paper-input-container no-label-float>
           <input id="nameserver[[index]]" is="iron-input" value="[[item]]"
               disabled="[[!canEdit_(editable, nameserversType_)]]"
               on-change="onValueChange_">
         </paper-input-container>
       </template>
     </div>
   </template>
   <script src="network_nameservers.js"></script>
 </dom-module>