Add LanguageModel, a keyed service that collects language info from CLD.

components/translate/content/browser/language_model_observer.h

+// Copyright 2016 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.
+
+#ifndef COMPONENTS_TRANSLATE_CONTENT_BROWSER_LANGUAGE_MODEL_OBSERVER_H_
+#define COMPONENTS_TRANSLATE_CONTENT_BROWSER_LANGUAGE_MODEL_OBSERVER_H_
+
+#include <map>
+
+#include "base/macros.h"
+#include "components/translate/content/browser/content_translate_driver.h"
+
+namespace translate {
+
+struct LanguageDetectionDetails;
+class LanguageModel;
+
+// Routes the language info from ContentTranslateDriver to LanguageModel.
+class LanguageModelObserver : public ContentTranslateDriver::Observer {
+ public:
+  explicit LanguageModelObserver(translate::LanguageModel* language_model);

[Bernhard Bauer, 2016/10/05 14:48:16]

Please explain the lifetime of |language_model|

[jkrcal, 2016/10/05 15:14:46]

This class got removed.

+  ~LanguageModelObserver() override;
+
+  // Called when the page language has been determined.
+  void OnLanguageDetermined(
+      const translate::LanguageDetectionDetails& details) override;
+
+ private:
+  translate::LanguageModel* language_model_;
+
+  DISALLOW_COPY_AND_ASSIGN(LanguageModelObserver);
+};
+
+}  // namespace translate
+
+#endif  // COMPONENTS_TRANSLATE_CONTENT_BROWSER_LANGUAGE_MODEL_OBSERVER_H_