Use ICU for string pluralization in the extension permission dialog.

chrome/browser/extensions/extension_install_prompt.cc

 // Copyright (c) 2012 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/extensions/extension_install_prompt.h"
 
 #include <map>
 
 #include "base/command_line.h"
 #include "base/message_loop/message_loop.h"
@@ skipping 329 matching lines @@
 
 string16 ExtensionInstallPrompt::Prompt::GetPermissionsHeading() const {
   return l10n_util::GetStringUTF16(kPermissionsHeaderIds[type_]);
 }
 
 string16 ExtensionInstallPrompt::Prompt::GetOAuthHeading() const {
   return l10n_util::GetStringFUTF16(kOAuthHeaderIds[type_], oauth_user_name_);
 }
 
 string16 ExtensionInstallPrompt::Prompt::GetRetainedFilesHeading() const {
-  return l10n_util::GetStringFUTF16(
-      IDS_EXTENSION_PROMPT_RETAINED_FILES,
-      base::IntToString16(GetRetainedFileCount()));
+  const int kRetainedFilesMessageIDs[6] = {
+      IDS_EXTENSION_PROMPT_RETAINED_FILES_DEFAULT,
+      IDS_EXTENSION_PROMPT_RETAINED_FILE_SINGULAR,
+      IDS_EXTENSION_PROMPT_RETAINED_FILES_ZERO,
+      IDS_EXTENSION_PROMPT_RETAINED_FILES_TWO,
+      IDS_EXTENSION_PROMPT_RETAINED_FILES_FEW,
+      IDS_EXTENSION_PROMPT_RETAINED_FILES_MANY,
+  };
+  std::vector<int> message_ids;
+  for (size_t i = 0; i < arraysize(kRetainedFilesMessageIDs); i++) {
+    message_ids.push_back(kRetainedFilesMessageIDs[i]);
+  }
+  return l10n_util::GetPluralStringFUTF16(message_ids, GetRetainedFileCount());
 }
 
 bool ExtensionInstallPrompt::Prompt::ShouldShowPermissions() const {
   return GetPermissionCount() > 0 || type_ == POST_INSTALL_PERMISSIONS_PROMPT;
 }
 
 void ExtensionInstallPrompt::Prompt::AppendRatingStars(
     StarAppender appender, void* data) const {
   CHECK(appender);
   CHECK_EQ(INLINE_INSTALL_PROMPT, type_);
@@ skipping 437 matching lines @@
   }
 
   if (AutoConfirmPrompt(delegate_))
     return;
 
   if (show_dialog_callback_.is_null())
     GetDefaultShowDialogCallback().Run(show_params_, delegate_, prompt_);
   else
     show_dialog_callback_.Run(show_params_, delegate_, prompt_);
 }