[search addon] Add classes to styled elements in dialogs

Closes #2776

addon/search/search.js

@@ -71,7 +71,7 @@
     return query;
   }
   var queryDialog =
-    'Search: <input type="text" style="width: 10em"/> <span style="color: #888">(Use /re/ syntax for regexp search)</span>';
+    'Search: <input type="text" style="width: 10em" class="CodeMirror-search-field"/> <span style="color: #888" class="CodeMirror-search-hint">(Use /re/ syntax for regexp search)</span>';
   function doSearch(cm, rev) {
     var state = getSearchState(cm);
     if (state.query) return findNext(cm, rev);
@@ -106,8 +106,8 @@
   });}
 
   var replaceQueryDialog =
-    'Replace: <input type="text" style="width: 10em"/> <span style="color: #888">(Use /re/ syntax for regexp search)</span>';
-  var replacementQueryDialog = 'With: <input type="text" style="width: 10em"/>';
+    'Replace: <input type="text" style="width: 10em" class="CodeMirror-search-field"/> <span style="color: #888" class="CodeMirror-search-hint">(Use /re/ syntax for regexp search)</span>';
+  var replacementQueryDialog = 'With: <input type="text" style="width: 10em" class="CodeMirror-search-field"/>';
   var doReplaceConfirm = "Replace? <button>Yes</button> <button>No</button> <button>Stop</button>";
   function replace(cm, all) {
     if (cm.getOption("readOnly")) return;