Move topSites API out of experimental

chrome/common/extensions/docs/static/permissions.html

 <div id="pageData-name" class="pageData">Optional Permissions</div>
 
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 <p id="classSummary">
   Use the <code>chrome.permissions</code> module to implement
   optional permissions. You can request optional permissions during your
   extension's regular application flow rather than at install time, so users
   understand why the permissions are needed and use only those that are
   necessary.
 </p>
@@ skipping 73 matching lines @@
   <li>contentSettings</li>
   <li>contextMenus</li>
   <li>cookies</li>
   <li>debugger</li>
   <li>history</li>
   <li>idle</li>
   <li>management</li>
   <li>notifications</li>
   <li>pageCapture</li>
   <li>tabs</li>
+  <li>topSites</li>
   <li>webNavigation</li>
   <li>webRequest</li>
   <li>webRequestBlocking</li>
 </ul>
 </p>
 
 <p class="note">
   <b>Version note:</b> This list is correct as of Chrome 17.
   More optional permissions might be allowed in future releases.
 </p>
@@ skipping 69 matching lines @@
   if (removed) {
     // The permissions have been removed.
   } else {
     // The permissions have not been removed (e.g., you tried to remove
     // required permissions).
   }
 });
 </pre>
 
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