Use ICU for string pluralization in the extension permission dialog.

ui/base/l10n/l10n_util_plurals.h

Index: ui/base/l10n/l10n_util_plurals.h
diff --git a/ui/base/l10n/l10n_util_plurals.h b/ui/base/l10n/l10n_util_plurals.h
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+// Copyright 2013 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.
+
+// This file contains utility functions for dealing with pluralization of
+// localized content.
+
+#ifndef UI_BASE_L10N_L10N_UTIL_PLURALS_H_
+#define UI_BASE_L10N_L10N_UTIL_PLURALS_H_
+
+#include <string>
+#include <vector>
+
+#include "base/memory/scoped_ptr.h"
+#include "third_party/icu/source/i18n/unicode/plurfmt.h"
+#include "third_party/icu/source/i18n/unicode/plurrule.h"
+
+namespace l10n_util {
+
+// Returns a PluralRules for the current locale.
+scoped_ptr<icu::PluralRules> BuildPluralRules();
+
+// Returns a PluralFormat from |message_ids|.  |message_ids| must be size 6 and
+// in order: default, singular, zero, two, few, many.
+scoped_ptr<icu::PluralFormat> BuildPluralFormat(
+    const std::vector<int>& message_ids);
+
+}  // namespace l10n_util
+
+#endif  // UI_BASE_L10N_L10N_UTIL_PLURALS_H_