Implemented event-dispatching for button clicks.

chrome/browser/chromeos/login/screens/eula_model.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_CHROMEOS_LOGIN_SCREENS_EULA_MODEL_H_
 #define CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_EULA_MODEL_H_
 
 #include "chrome/browser/chromeos/login/screens/base_screen.h"
 #include "url/gurl.h"
 
 namespace chromeos {
 
 class BaseScreenDelegate;
 class EulaView;
 
 // Allows us to get info from eula screen that we need.
 class EulaModel : public BaseScreen {
  public:
+  static const char kUserActionAcceptButtonClicked[];
+  static const char kUserActionBackButtonClicked[];
+  static const char kContextKeyUsageStatsEnabled[];
+
   explicit EulaModel(BaseScreenDelegate* base_screen_delegate);
   virtual ~EulaModel();
 
   // BaseScreen implementation:
   virtual std::string GetName() const override;
 
   // Returns URL of the OEM EULA page that should be displayed using current
   // locale and manifest. Returns empty URL otherwise.
   virtual GURL GetOemEulaUrl() const = 0;
 
-  // Called when accept button was clicked.
-  virtual void OnAcceptButtonClicked() = 0;
-
-  // Called when back button was clicked.
-  virtual void OnBackButtonClicked() = 0;
-
   // Initiate TPM password fetch. Will call actor's OnPasswordFetched() when
   // done.
   virtual void InitiatePasswordFetch() = 0;
 
   // Returns true if usage statistics reporting is enabled.
   virtual bool IsUsageStatsEnabled() const = 0;
 
   // This method is called, when view is being destroyed. Note, if model
   // is destroyed earlier then it has to call SetModel(NULL).
   virtual void OnViewDestroyed(EulaView* view) = 0;
 };
 
 }  // namespace chromeos
 
 #endif  // CHROME_BROWSER_CHROMEOS_LOGIN_SCREENS_EULA_MODEL_H_