Options/MD Settings: use new prefs to drive import data dialog

chrome/browser/resources/options/import_data_overlay.html

 <div id="import-data-overlay" class="page" hidden>
   <div class="close-button"></div>
   <h1 i18n-content="importDataOverlay"></h1>
   <div class="content-area">
     <div class="import-data-configure">
       <div id="import-from-div">
         <span i18n-content="importFromLabel"></span>
         <select id="import-browsers">
           <option i18n-content="importLoading"></option>
         </select>
       </div>
       <div id="import-checkboxes">
         <div i18n-content="importDescription"></div>
         <div class="checkbox controlled-setting-with-label"
               id="import-history-with-label">
           <label>
-            <input id="import-history" type="checkbox" pref="import_history">
+            <input id="import-history" type="checkbox"
+                pref="import_dialog_history">
             <span>
               <span i18n-content="importHistory"></span>
-              <span class="controlled-setting-indicator" pref="import_history">
+              <span class="controlled-setting-indicator"
+                  pref="import_dialog_history">
               </span>
             </span>
           </label>
         </div>
         <div class="checkbox controlled-setting-with-label"
             id="import-favorites-with-label">
           <label>
             <input id="import-favorites" type="checkbox"
-                pref="import_bookmarks">
+                pref="import_dialog_bookmarks">
             <span>
               <span i18n-content="importFavorites"></span>
               <span class="controlled-setting-indicator"
-                  pref="import_bookmarks"></span>
+                  pref="import_dialog_bookmarks"></span>
             </span>
           </label>
         </div>
         <div class="checkbox controlled-setting-with-label"
             id="import-passwords-with-label">
           <label>
             <input id="import-passwords" type="checkbox"
-                pref="import_saved_passwords">
+                pref="import_dialog_saved_passwords">
             <span>
               <span i18n-content="importPasswords"></span>
               <span class="controlled-setting-indicator"
-                  pref="import_saved_passwords"></span>
+                  pref="import_dialog_saved_passwords"></span>
             </span>
           </label>
         </div>
         <div class="checkbox controlled-setting-with-label"
             id="import-search-with-label">
           <label>
             <input id="import-search" type="checkbox"
-                pref="import_search_engine">
+                pref="import_dialog_search_engine">
             <span>
               <span i18n-content="importSearch"></span>
               <span class="controlled-setting-indicator"
-                  pref="import_search_engine"></span>
+                  pref="import_dialog_search_engine"></span>
             </span>
           </label>
         </div>
         <div class="checkbox controlled-setting-with-label"
             id="import-autofill-form-data-with-label">
           <label>
             <input id="import-autofill-form-data" type="checkbox"
-                pref="import_autofill_form_data">
+                pref="import_dialog_autofill_form_data">
             <span i18n-content="importAutofillFormData"></span>
           </label>
           <span class="controlled-setting-indicator"
-              pref="import_autofill_form_data"></span>
+              pref="import_dialog_autofill_form_data"></span>
         </div>
       </div>
     </div>
     <div class="import-data-success" hidden>
       <div id="import-success-header">
         <strong i18n-content="importSucceeded"></strong>
       </div>
       <div id="import-success-image"></div>
       <div id="import-find-your-bookmarks">
         <span i18n-content="findYourImportedBookmarks"></span>
@@ skipping 30 matching lines @@
       <div class="action-area-right">
         <div class="button-strip">
           <button id="import-data-confirm" class="default-button"
               i18n-content="done">
           </button>
         </div>
       </div>
     </div>
   </div>
 </div>