Only show prefer network checkbox for networks stored on user profile.

chrome/browser/resources/options/chromeos/internet_detail.html

 <div id="detailsInternetPage" class="page" hidden>
   <h1 id="inetTitle"></h1>
   <!-- Navigation tabs -->
   <div id="details-tab-strip" class="subpages-nav-tabs">
     <span id="wifiNetworkNavTab" class="tab wifi-details"
         tab-contents="wifiNetworkTab">
       <span class="tab-label"
           i18n-content="wifiNetworkTabLabel"></span>
       <span class="active-tab-label" i18n-content="wifiNetworkTabLabel"></span>
     </span>
@@ skipping 36 matching lines @@
     <section>
       <table class="ssid-table">
         <tr>
           <td class="option-name" i18n-content="inetSsid"></td>
           <td id="inetSsid" class="option-value"></td>
         </tr>
       </table>
     </section>
     <section>
       <table class="option-control-table">
-        <tr>
-          <td colspan="2">
+        <tr class="prefer-network">
+          <td>
             <div class="checkbox">
               <label>
                 <input id="preferNetworkWifi" type="checkbox">
                 <span i18n-content="inetPreferredNetwork"></span>
               </label>
             </div>
           </td>
         </tr>
-        <tr>
-          <td colspan="2">
+        <tr class="auto-connect-network">
+          <td>
             <div class="checkbox">
               <label>
                 <input id="autoConnectNetworkWifi" type="checkbox">
                 <span i18n-content="inetAutoConnectNetwork"></span>
               </label>
             </div>
           </td>
         </tr>
       </table>
     </section>
@@ skipping 263 matching lines @@
     <button id="detailsInternetLogin"
             i18n-content="connect_button"></button>
     <button id="detailsInternetDisconnect"
             i18n-content="disconnect_button"></button>
     <button id="activateDetails"
             i18n-content="activate_button"></button>
     <button id="buyplanDetails"
             i18n-content="buyplan_button"></button>
   </div>
 </div>