Merge 159156 - Extensions Docs Server: Fix headings with no IDs

chrome/common/extensions/docs/templates/intros/devtools_panels.html

 <p id="classSummary">
 Use the <code>chrome.devtools.panels</code> module to integrate
 your extension into Developer Tools window UI: create your own panels, access
 existing panels, and add sidebars.
 </p><p>
 See <a href="devtools.html">DevTools APIs summary</a> for
 general introduction to using Developer Tools APIs.
 </p>
 
-<h2>Overview</h2>
+<h2 id="overview">Overview</h2>
 
 <p>
 Each extension panel and sidebar is displayed as a separate HTML page. All
 extension pages displayed in the Developer Tools window have access to all
 modules in <code>chrome.devtools</code> API, as well as to
 <a href="extension.html">chrome.extension</a> API. Other extension APIs are not
 available to the pages within Developer Tools window, but you may invoke them
 by sending a request to the background page of your extension, similarly to how
 it's done in the <a href="overview.html#contentScripts">content scripts</a>.
 </p><p>
@@ skipping 33 matching lines @@
 
 <img src="{{static}}/images/devtools-panels.png"
      style="margin-left: 20px"
      width="686" height="289"
      alt="Extension icon panel on DevTools toolbar" />
 </p>
 
 <p>
 You can find examples that use this API in
 <a href="samples.html#Chrome&#32;Query">Samples</a>.
-</p>
+</p>