When page translation state is updated, just ask the toolbar to update, don't

chrome/browser/ui/browser_content_translate_driver_observer.h

-// 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.
-
-#ifndef CHROME_BROWSER_UI_BROWSER_CONTENT_TRANSLATE_DRIVER_OBSERVER_H_
-#define CHROME_BROWSER_UI_BROWSER_CONTENT_TRANSLATE_DRIVER_OBSERVER_H_
-
-#include "components/translate/content/browser/content_translate_driver.h"
-
-#include "base/basictypes.h"
-#include "base/compiler_specific.h"
-
-class Browser;
-
-// Implementation of ContentTranslateDriver::Observer for Browser. This observes
-// wether Translate is enabled or not, and updates toolbar in response to
-// changes in state of translate.
-class BrowserContentTranslateDriverObserver
-    : public translate::ContentTranslateDriver::Observer {
- public:
-  explicit BrowserContentTranslateDriverObserver(Browser* browser);
-
-  ~BrowserContentTranslateDriverObserver() override;
-
-  // Overridden from ContentTranslateDriver::Observer
-  void OnIsPageTranslatedChanged(content::WebContents* source) override;
-  void OnTranslateEnabledChanged(content::WebContents* source) override;
-
- private:
-  Browser* browser_;
-
-  DISALLOW_COPY_AND_ASSIGN(BrowserContentTranslateDriverObserver);
-};
-
-#endif  // CHROME_BROWSER_UI_BROWSER_CONTENT_TRANSLATE_DRIVER_OBSERVER_H_