Update WebUI calls to use extensions namespace, update IDs in c/b/r/extensions

chrome/browser/resources/extensions/extension_commands_overlay.html

 <!--
  * Copyright (c) 2012 The Chromium Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be found
  * in the LICENSE file.
 -->
-<div id="extensionCommandsOverlay" class="page">
+<div id="extension-commands-overlay" class="page">
   <div class="close-button"></div>
   <h1 i18n-content="extensionCommandsOverlay"></h1>
   <div class="content-area">
     <div id="extension-command-list"
          class="empty-extension-commands-list"></div>
     <div id="no-commands" hidden>
       <span id="no-extensions-commands-message"
             i18n-content="extensionCommandsEmpty"></span>
     </div>
   </div>
   <div class="action-area">
     <div class="action-area-right">
       <div class="button-strip">
-        <button id="extensionCommandsDismiss" i18n-content="ok"></button>
+        <button id="extension-commands-dismiss" i18n-content="ok"></button>
       </div>
     </div>
   </div>
 </div>
 
 <div id="template-collection-extension-commands" hidden>
   <div class="extension-command-list-extension-item-wrapper">
     <div class="extension-command-list-extension-item">
       <div class="extension-command-extension-details">
         <div>
@@ skipping 13 matching lines @@
               ><span class="command-shortcut clearable"
                   ><img class="command-clear"
                         src="chrome://theme/IDR_EXTENSION_COMMAND_CLOSE"
                   ><span class="command-shortcut-text" tabindex="0"
               ></span></span></span>
         </div>
       </div>
     </div>
   </div>
 </div>