MD Settings: drop confusing "Enable guest browsing" secondary text

chrome/browser/resources/settings/people_page/people_page.html

 <link rel="import" href="chrome://resources/cr_elements/icons.html">
 <link rel="import" href="chrome://resources/html/i18n_behavior.html">
 <link rel="import" href="chrome://resources/html/icon.html">
 <link rel="import" href="chrome://resources/html/polymer.html">
 <link rel="import" href="chrome://resources/html/web_ui_listener_behavior.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/neon-animation/neon-animatable.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-button/paper-button.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-checkbox/paper-checkbox.html">
 <link rel="import" href="chrome://resources/polymer/v1_0/paper-icon-button/paper-icon-button-light.html">
 <link rel="import" href="chrome://resources/cr_elements/cr_dialog/cr_dialog.html">
@@ skipping 238 matching lines @@
                     on-tap="onEasyUnlockTurnOffTap_">
                   $i18n{easyUnlockTurnOffButton}
                 </paper-button>
               </template>
             </div>
           </div>
         </template>
 </if>
 
         <div id="manage-other-people-subpage-trigger"
-            class="settings-box two-line" on-tap="onManageOtherPeople_"
-            actionable>
-          <div class="start">
-            $i18n{manageOtherPeople}
-            <div class="secondary">$i18n{manageOtherPeopleDescription}</div>
-          </div>
+            class="settings-box" on-tap="onManageOtherPeople_" actionable>
+          <div class="start">$i18n{manageOtherPeople}</div>
           <button class="subpage-arrow" is="paper-icon-button-light"></button>
         </div>
 
 <if expr="not chromeos">
         <div class="settings-box" on-tap="onImportDataTap_" actionable>
           <div class="start">$i18n{importTitle}</div>
           <button class="subpage-arrow" is="paper-icon-button-light"></button>
         </div>
 </if>
 
@@ skipping 92 matching lines @@
 
 <if expr="chromeos">
     <template is="dom-if" if="[[easyUnlockEnabled_]]">
       <easy-unlock-turn-off-dialog id="easyUnlockTurnOffDialog">
       </easy-unlock-turn-off-dialog>
     </template>
 </if>
   </template>
   <script src="people_page.js"></script>
 </dom-module>