Find-in-page should not ding while deleting characters.

chrome/browser/find_bar_controller.cc

 // Copyright (c) 2009 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 "chrome/browser/find_bar_controller.h"
 
 #include "app/l10n_util.h"
 #include "build/build_config.h"
 #include "chrome/browser/find_bar.h"
 #include "chrome/browser/tab_contents/navigation_entry.h"
@@ skipping 103 matching lines @@
 void FindBarController::Observe(NotificationType type,
                                 const NotificationSource& source,
                                 const NotificationDetails& details) {
   if (type == NotificationType::FIND_RESULT_AVAILABLE) {
     // Don't update for notifications from TabContentses other than the one we
     // are actively tracking.
     if (Source<TabContents>(source).ptr() == tab_contents_) {
       UpdateFindBarForCurrentResult();
       if (tab_contents_->find_result().final_update() &&
           tab_contents_->find_result().number_of_matches() == 0) {
-        find_bar_->AudibleAlert();
+        const string16& last_search = tab_contents_->previous_find_text();
+        const string16& current_search = tab_contents_->find_text();
+        if (last_search.find(current_search) != 0)

[Peter Kasting, 2009/10/26 21:04:33]

Nit: If you want, you can inline those temps into here.

+          find_bar_->AudibleAlert();
       }
     }
   } else if (type == NotificationType::NAV_ENTRY_COMMITTED) {
     NavigationController* source_controller =
         Source<NavigationController>(source).ptr();
     if (source_controller == &tab_contents_->controller()) {
       NavigationController::LoadCommittedDetails* commit_details =
           Details<NavigationController::LoadCommittedDetails>(details).ptr();
       PageTransition::Type transition_type =
           commit_details->entry->transition_type();
@@ skipping 66 matching lines @@
   if (find_result.number_of_matches() > -1) {
     if (last_reported_matchcount_ > 0 &&
         find_result.number_of_matches() == 1 &&
         !find_result.final_update())
       return;  // Don't let interim result override match count.
     last_reported_matchcount_ = find_result.number_of_matches();
   }
 
   find_bar_->UpdateUIForFindResult(find_result, tab_contents_->find_text());
 }