Options: Style cleanup - id attribute first.

chrome/browser/resources/options/about_page.html

-<div class="page" id="aboutPage" hidden>
+<div id="aboutPage" class="page" hidden>
   <h1 i18n-content="product"></h1>
   <div id="aboutPageLessInfo">
     <section>
       <div>
         <!-- White space is significant between spans. -->
         <div><span i18n-content="firmware"></span> <span id="osFirmware0">
           <span class="loading" i18n-content="loading"></span></span></div>
         <div><span i18n-content="os"></span> <span id="osVersion0">
           <span class="loading" i18n-content="loading"></span></span></div>
         <div>
           <span i18n-content="browser"></span>
           <span i18n-content="browser_version"></span>
         </div>
         <div>
-          <button class="link-button" id="moreInfoButton"
-                  i18n-content="more_info"></button>
+          <button id="moreInfoButton" class="link-button"
+              i18n-content="more_info"></button>
         </div>
       </div>
     </section>
   </div>
   <div id="aboutPageMoreInfo" hidden>
     <section>
       <h3 i18n-content="channel"></h3>
       <div>
         <select id="channelSelect">
           <option value="stable-channel" i18n-content="stable"></option>
           <option value="beta-channel" i18n-content="beta"></option>
           <option value="dev-channel" i18n-content="dev"></option>
         </select>
-        <div hidden id="channelWarningBlock">
+        <div id="channelWarningBlock" hidden>
           <div id="channelWarning" i18n-content="channel_warning_header"></div>
           <div i18n-content="channel_warning_text"></div>
         </div>
       </div>
     </section>
     <section>
       <h3 i18n-content="firmware"></h3>
       <div id="osFirmware1">
         <span class="loading" i18n-content="loading"></span>
     </section>
@@ skipping 52 matching lines @@
   </section>
   <section>
     <div>
       <div>
         <div id="updateIcon" class="update-icon up-to-date"></div>
         <span id="updateStatus" i18n-content="update_status"></span>
       </div>
       <div>
         <!-- TODO seanparent: fill in last checked. -->
         <!-- <span i18n-content="last_check"></span> -->
-        <button disabled id="checkNow" i18n-content="check_now"></button>
+        <button id="checkNow" i18n-content="check_now" disabled></button>
       </div>
     </div>
   </section>
 </div>