Provide description_class in search provider.

components/omnibox/base_search_provider.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "components/omnibox/base_search_provider.h"
 
 #include "base/i18n/case_conversion.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
 #include "components/metrics/proto/omnibox_event.pb.h"
@@ skipping 204 matching lines @@
         kACMatchPropertyInputText, base::UTF16ToUTF8(input.text()));
     match.RecordAdditionalInfo(
         kACMatchPropertyContentsPrefix,
         base::UTF16ToUTF8(suggestion.match_contents_prefix()));
     match.RecordAdditionalInfo(
         kACMatchPropertyContentsStartIndex,
         static_cast<int>(
             suggestion.suggestion().length() - match.contents.length()));
   }
 
-  if (!suggestion.annotation().empty())
+  if (!suggestion.annotation().empty()) {
     match.description = suggestion.annotation();
+    AutocompleteMatch::AddLastClassificationIfNecessary(
+        &match.description_class, 0, ACMatchClassification::NONE);
+  }
 
   // suggestion.match_contents() should have already been collapsed.
   match.allowed_to_be_default_match =
       (!in_keyword_mode || suggestion.from_keyword_provider()) &&
       (base::CollapseWhitespace(input.text(), false) ==
        suggestion.match_contents());
 
   // When the user forced a query, we need to make sure all the fill_into_edit
   // values preserve that property.  Otherwise, if the user starts editing a
   // suggestion, non-Search results will suddenly appear.
@@ skipping 235 matching lines @@
 }
 
 void BaseSearchProvider::OnDeletionComplete(
     bool success, SuggestionDeletionHandler* handler) {
   RecordDeletionResult(success);
   SuggestionDeletionHandlers::iterator it = std::find(
       deletion_handlers_.begin(), deletion_handlers_.end(), handler);
   DCHECK(it != deletion_handlers_.end());
   deletion_handlers_.erase(it);
 }