fixup keyMap

IPython/html/static/edit/js/menubar.js

@@ -77,7 +77,7 @@ define([
         this.element.find('#menu-keymap-default').click(function () {
             editor.update_codemirror_options({
                 vimMode: false,
-                keyMap: null
+                keyMap: 'default'
             });
         });
         this.element.find('#menu-keymap-sublime').click(function () {

IPython/html/templates/edit.html

@@ -47,7 +47,7 @@ data-file-path="{{file_path}}"
                 <li id="menu-find"><a href="#">Find</a></li>
                 <li id="menu-replace"><a href="#">Find &amp; Replace</a></li>
                 <li class="divider"></li>
-                <li>Key Map</li>
+                <li class="dropdown-header">Key Map</li>
                 <li id="menu-keymap-default"><a href="#">Default<i class="fa"></i></a></li>
                 <li id="menu-keymap-sublime"><a href="#">Sublime Text<i class="fa"></i></a></li>
                 <li id="menu-keymap-vim"><a href="#">Vim<i class="fa"></i></a></li>