Remove pp_ifdef from resource files in chrome/browser and chrome/renderer.

chrome/browser/resources/options/sync_section.html

-<if expr="not pp_ifdef('chromeos')">
+<if expr="not chromeos">
 <section id="sync-section">
   <h3 i18n-content="sectionTitleSync"></h3>
 </if>
-<if expr="pp_ifdef('chromeos')">
+<if expr="chromeos">
 <div id="sync-section">
 </if>
 
   <div id="sync-overview" class="settings-row" hidden>
     <p i18n-content="syncOverview"></p>
     <a i18n-values="href:syncLearnMoreURL" i18n-content="learnMore"
         target="_blank"></a>
   </div>
 
-<if expr="pp_ifdef('chromeos')">
+<if expr="chromeos">
   <div id="account-picture-wrapper">
     <div id="account-picture-control">
       <input type="image" id="account-picture" tabindex="0"
           alt="" i18n-values="aria-label:changePicture">
       <div id="change-picture-caption" i18n-content="changePicture"></div>
     </div>
     <span id="account-picture-indicator" class="controlled-setting-indicator">
     </span>
   </div>
   <div id="sync-general">
-</if>  <!-- pp_ifdef('chromeos') -->
+</if>  <!-- chromeos -->
 
     <div id="sync-status" class="settings-row" hidden>
       <span id="sync-status-text"></span>
       <button id="sync-action-link" class="link-button"></button>
     </div>
 
-<if expr="pp_ifdef('chromeos')">
+<if expr="chromeos">
     <div class="checkbox">
       <span class="controlled-setting-with-label">
         <input id="enable-screen-lock" type="checkbox"
             pref="settings.enable_screen_lock">
         <span>
           <label for="enable-screen-lock" i18n-content="enableScreenlock">
           </label>
           <span class="controlled-setting-indicator"
               pref="settings.enable_screen_lock">
           </span>
         </span>
       </span>
     </div>
   </div>
-</if>  <!-- pp_ifdef('chromeos') -->
+</if>  <!-- chromeos -->
 
   <div id="sync-buttons" class="settings-row">
     <button id="start-stop-sync" hidden></button>
     <span id="start-stop-sync-indicator"
         class="controlled-setting-indicator" hidden>
     </span>
     <button id="customize-sync" i18n-content="customizeSync"
         pref="sync.managed" hidden>
     </button>
-<if expr="pp_ifdef('chromeos')">
+<if expr="chromeos">
     <button id="manage-accounts-button"
         i18n-content="manageAccountsButtonTitle">
     </button>
-</if>  <!-- pp_ifdef('chromeos') -->
+</if>  <!-- chromeos -->
     <div id="enable-auto-login-checkbox" class="checkbox" hidden>
       <label>
         <input id="enable-auto-login" pref="autologin.enabled"
             metric="Options_Autologin" type="checkbox">
         <span i18n-content="autologinEnabled"></span>
       </label>
     </div>
   </div>
 
-<if expr="not pp_ifdef('chromeos')">
+<if expr="not chromeos">
 </section>
 </if>
-<if expr="pp_ifdef('chromeos')">
+<if expr="chromeos">
 </div>
 </if>